婚約指輪に使われたダイヤモンドの歴史

 

ジャック・オグデンFGAが、婚約指輪に使われていたダイヤモンドの歴史について見ていきます 。この習慣がどれほど古いものなのか、少し驚くかもしれません...

ここで皆さんに質問があります。婚約指輪に関する次の文章を読んでください。「婚約指輪に は、250から2000ドルと価格に幅があるが、現代ファッションにおいてはダイヤモンドのソリテ ール(一石のダイヤモンドを留めたリング)と定める」。これがいつ書かれたものであると思 いますか?第二次世界大戦の前でしょうか、後でしょうか?

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Breaking down the Misunderstandings about Precious Coral

Inspired by Pantone’s ‘Color of the Year 2019’, Rui Galopim de Carvalho FGA DGA dives into the underwater world of precious coral and addresses some of the misunderstandings around its use in the jewellery industry.

The colour of many precious corals has been announced as the ‘Color of the Year 2019’ by Pantone, the US-based company known for its proprietary colour system widely used in the printing industry. Under the name ‘Pantone 16-1546 Living Coral’ this colour code alludes to the pink to red colour that is commonly associated with corals. A clarification is therefore in order to properly understand what it is meant by coral in the jewellery industry.

Coral is the collective name that has been used to describe a very large number of species of cnidarians of the Anthozoa class. Among these more than 7,300 species, we encounter the endangered shallow-water coral species in Australia’s Great Barrier Reef and elsewhere that have been suffering from bleaching and death as a result of climate change and ocean acidification.

Read more: Understanding the 'Coral Conversation'

This dramatic situation for the equilibrium of the planet’s marine ecosystems has negatively impacted on the reputation of coral as a luxury product. It happens that the corals used in the jewellery industry do not live in the same ecosystem as those endangered reef corals. This is why those that are used jewellery and decorative arts have been designated as ‘precious corals’ by CIBJO, the World Jewellery Confederation, separating them from the ‘common corals’ and even more dramatically from the endangered reef corals.

What are Precious Corals? 

These are corals most used in high-end jewellery and decoration and are limited to species belonging to the Corallidae family, particularly from the genus Corallium, Pleurocorallium and Hemicorallium. It is in some of these groups that we can find the red and pink, sometimes salmon-coloured and often white varieties with porcelain like lustre after polishing that relate to this year’s Pantone colour.

Precious Coral and Common Coral Gem A Blog CROPA parcel of polished small branches of Deep Sea coral (Hemicorallium laauense). Photo courtesy of Liverino 1894.

Although a few varieties of red and pink coral were listed for the monitoring of the trade in Appendix III of CITES at the request of China in 2008 (Corallium elatius, C. japonicum, C. konojoi and C. secundum[sic]), no precious corals are listed in the more restrictive CITES Appendixes I and II.

It must be said that the recommendation for monitoring expired in 2013, being extended until 2016, and that for the next CITES meeting in 2019, no further action is to be proposed for precious corals. Current fishing regulations in the Mediterranean, Taiwan and Japan have played an important role in resource management of precious corals and more initiatives are being implemented to further the issue.

Let’s then establish what are the precious coral species currently recognised by the trade:

Corallium japonicum (Aka, Moro or Oxblood coral), the dark red to very dark red corals with a lengthwise white interior which live at depths of 80 to 300 in Japan

Pleurocorallium elatius comprising of two varieties: the so called Momo, Cerasuolo or Satsuma coral, a bright red, salmon, orange and flesh colour with a lengthwise white interior and its albino variety, known in the trade as Angel Skin, Boké or Magai coral, a delicate flesh pink, with different colour intensities, which live at depths of 150 to 300 meters mainly off the coasts of Japan and Taiwan

Pleurocorallium konojoi (Pure White or Shiro coral), the milky white and sometimes with red or pink specks, that live at depths of 80 to 300 meters in the South China Sea and off the coast of Hainan

Pleurocorallium secundum (Midway, Rosato or White/Pink), the veined white or pink, and sometimes with red specks, or uniform clear pink, that lives at depths of 400 to 600 meters off the coasts of Hawaii and Midway Island

Hemicorallium laauense (Deep Sea or Shinkai coral), the bright white, clear pink or white pomegranate with red veins or spots which live at depths of 1000 to 2000 meters off the coast of Midway Island, north-west of Emperor Seamount

Hemicorallium regale (Garnet coral), the pomegranate colour with different shades of uniform pink that live at depths of 350 to 600 metres off the coast of Hawaii

Hemicorallium sulcatum (Misu, Missu or Miss coral), the pink to violet uniform colour which live at depths of 100 to 300 metres in the Philippines northern coastal waters

Corallium rubrum (Sardinian or Mediterranean coral), the historically and culturally famous uniform red with medium to strong saturation that live at depths up to 1,000 metres (harvested only bellow 50 meters) in the Mediterranean and in the Atlantic Ocean off the coast of North Africa, including in the waters of the Canary Islands and Cape VerdePrecious Coral and Common Coral Gem A Blog 1
The taxonomy of precious corals (in Pantone 'Living Coral' colour) and Common corals (in grey).

What are Common Corals? 

Apart from the above mentioned Corallidae family species, there are a few other corals that have been used for decoration and in jewellery. These, defined as common corals, include mostly calcareous types, like sponge corals, bamboo corals and blue corals as well as black and golden corals, which have non-calcareous exoskeletons. Many of these must undergo treatment (e.g. bleaching, dyeing, impregnation) to be used as gem materials.

Contrarily to precious corals, certain common coral species are listed in CITES Appendix II, e.g. black coral (Antipatharia spp.), blue coral (Heliopora coerulea), stony corals (Scleractinia spp.), organpipe corals (Tubiporidae family), fire corals (Milleporidae family) and lace corals (Stylasteridae family).

Reef coral preservation should be on the top of the agenda not only of the jewellery industry but also of society as a whole, mainly by reducing the carbon impact of civilization that is responsible for climate change and ocean acidification.

Precious Coral and Common Coral Gem A Blog The Impact of Coral BleachingThe dramatic effects of bleaching in coral reef (before and after). Image courtesy of The Ocran Agency / XL Catlin Seaview Survey/Coral Reef Image Bank.

CIBJO recently argued through its Coral Commission president Vincenzo Liverino under the banner of a ‘Promise of Sustainability’ at the 21st FEEG Symposium and CIBJO Seminar on Responsible Sourcing and Sustainability held at the VicenzaOro show, Italy in January, that it is a task of the industry and first of all of the coral industry to set an example by embracing the ‘Jewellery Industry Measurement Initiative’ promoted by CIBJO to help companies within the jewellery industry understand their environmental impact, reduce their carbon footprint, and protect themselves and the industry as a whole.

The need for education of both the trade and the consumer in these matters is therefore of prime importance to correct what was a lack of consistency in the terminology used to describe precious coral, to inform the public of about the biology, ecology, history and legacy of precious coral and to raise public awareness of issues related to the sustainability of coral in general, and precious coral in particular, predominantly in light of the challenges posed by global warming and ocean acidification.

Do you want to broaden your knowlege of organics and gemstones? Discover Gem-A Short Courses and Workshops, or explore our Gemmology Foundation and Diploma Courses

This article was first published in the Spring 2019 edition of Gems&Jewellery. To find out more and read the magazine archive online, please click here

Cover image: Two necklaces: Angel’s skin (Boké or Magai) coral, the albino variety of Pleurocorallium elatius, and Oxblood (Aka or Moro), the deep red variety of Corallium japonicum. Image courtesy of Chii Lih Coral.

Images courtesy of the author unless otherwise stated.

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How to Identify Antique Edwardian Jewellery

Understanding how to identify jewellery from different eras and design movements is essential for historians, valuers and antique collectors. Here, Starla Turner FGA GG offers us a glimpse into the refined and elegant world of Edwardian jewellery and describes the motifs that make pieces recognisable. 

Fashion of the Edwardian Era

The short reign of King Edward VII (1901 to 1910), his court, his sporting lifestyle and his wife Alexandra of Denmark were a breath of fresh air to fashion at the close of the 1800s. Jewellery motifs changed accordingly, with intricate and gracefully symmetrical, diamond-encrusted and lacy designs adorning the neckline, chiffon gowns and the ‘up-do’ hair styles of the well-to-do. Delicate scrolls, leaves, ribbon bows, hearts, circles, swooping swags (or garlands as they were later called), and veil-like twinkling jewellery complimented a new sophisticated style.

To me, Edwardian designs look like a frozen moment – curled in movement, shimmering, draping, scrolling, swaging, circling – just waiting to be worn and move again. The Edwardian femininity, fluidity, and fineness are unmistakeable. Iconic pieces have hinges, dangles, swags, articulation, and tiny swinging gemstone droplets evoking a liquidity and liveliness.

Queen Alexandra loved the uncomfortable but fashionable ‘dog collar’ plaque style necklace, often backed by black velvet. The style transitioned into a column of 6-16 rows of pearls — a challenge to wear for sure. Changing dress necklines brought changing neck ornamentation. A good example is the rivière necklace – a neck-encircling strand of graduating, millegraine-edged, bezel set diamonds — sometimes worn as two bracelets.

Read more: The Tale of the Mouawad-Tereschenko Blue Diamond

We see up to 72-inch long strands of ‘spectacle set’ diamonds, a minimalist technique where only a thin wire wraps the diamond girdle and small side jump rings attach to the next gem. The lavaliere is an articulating drop suspended from a matching design element and attached directly to a thin, fancy link chain. The negligee necklace has two drops, often on different lengths of chain, attached to one design element and a simple chain. Basic pendants have diamond-set, double side engraved, tapered bales that hang on thin, intricately designed chains.

Tiaras of the Edwardian Era 

The Edwardian era also saw a fascination with tiaras. Bandeaus, like tiaras, could double as necklaces or bracelets — screw holes or extra loops in the backside show their transitioning versatility. Sautoirs, long bundles of pearl strands ending with tassels, were wrapped around necks, waists, bodices and arms. Bracelets show symmetrical repeating designs in either full length or top half only designs. A new trend was the more diminutive, tapering diamond and coloured stone bracelets with articulating or stretching metal links in the rear. Rings were becoming wider and domed just enough to accommodate the depth of the centre diamond.Edwardian Swan Brooch Back by Lang Antiques Gem A Blog Antique Jewellery VintageThe back of a beautiful swan pin, showing calibré cut emeralds and the 'swinging' diamonds typical of the Edwardian era. 

The Rise of Platinum in Edwardian Jewellery 

Solid platinum or platinum over gold suited the pale, pastel and feminine fashion palette. Platinum was a new white metal that, unlike silver, didn’t stain the skin and clothing and could strongly, but delicately, hold the all-important diamond. Initially, platinum was bonded to yellow gold, a technique created to add value and acceptability to this new, inexpensive and unappreciated metal.

The vast majority of Edwardian diamond pieces I see are hand-fabricated (cut, sawn, rolled, drawn and assembled). Cast pieces are uncommon due to the high heat required to melt the metal. Edwardian jewellery is typically assembled from fewer parts, likely due to the visibility of the yellow gold-based solder that was used.

Read more: The Fascinating History of Platinum Jewellery 

This yellowish solder in seams disappeared into a whiter hue after WWI when white gold made its debut. In addition, platinum is a noble metal – it does not tarnish – so the tarnish one sees is from the solder mix of gold, silver and platinum. Therefore, tarnish and patina can add provenance as it develops with age. Sometimes re-polishing the metal can remove a bit of authenticity.

Diamonds in Edwardian Jewellery 

South Africa supplied a plethora of diamonds. While the Second Boer War (Oct 1899 –May 1902) had an impact on pricing, the demand continued. The diamond circular saw, the fixed dop (the clamp that holds a diamond being cut) for precise angles, bruiting machine advancements and electricity reduced cutting times. They also resulted in the more brilliant, rounder European-cut diamond.

Marquise and pear-shapes also became more available. The beauty of a finished diamond became the focus, rather than the weight retention.

Edwardian Brooch by Lang Antiques Gem A Blog Antique Jewellery VintageAn Edwardian era pin that would have doubled as a tiara or hair ornament. 

Later into the period, single cut diamonds replaced the rose cuts of the past. With faster cutting techniques, the sparkling 17 facet single cut became the perfect accent to delicate jewellery. Smaller Swiss-cut and small European-cut diamonds also help date this era. Old mine cutting was phased out by the end of the era, but diamonds were still recycled into new pieces.

Pearls in Edwardian Jewellery 

Pearls were second to diamond in popularity and suited the monochromatic styling of the era. Their ethereal sheen worked beautifully with gossamer fabrics. Articulating drops gave the appearance of water and added the wonderful element of movement in open work designs. Due to the rarity of natural pearls (cultured pearls were about to debut in high numbers) seed pearls of 3.5mm or smaller were cut into two useable halves and flush mounted onto metal.

Read more: Understanding Diamond Colours with the Aurora Pyramid of Hope 

The American and Scottish freshwater pearls reveal a whiter, wrinkled skin whereas the Indian Ocean and Gulf saltwater pearls are creamy to light grey (often turning grey from a soap that has been used to clean them) and smooth skinned. Uncut and larger natural pearls are often button or oval shaped. The very round cultured pearls in Edwardian pieces tend to be replacement stones.

Gemstones in Edwardian Jewellery 

Sapphire, emerald, opal, ruby, amethyst, demantoid garnet, moonstone or peridots were recessed into a circle of diamonds — enter the halo ring! Look for treasures in these old pieces: Kashmir sapphires, Burmese rubies, Russian demantoid garnets, Australian black opals.

Edwardian Oval Diamond Brooch by Lang Antiques Gem A Blog Antique Jewellery VintageA pierced-out brooch from the Edwardian era.

Calibré cut stones, the tiny (1-2mm), straight-sided, geometrically shaped ruby, sapphire, emerald and amethyst, were cut to fit into channels and dance around designs. The newly-created and evenly-coloured synthetic sapphire and ruby calibré appear in late Edwardian pieces. Black enamel or onyx also provided contrast to the all white look as it transitioned from the mourning jewellery age.

A platinum and diamond central ornamentation could also be highlighted with a larger splash of colour from background bases of pastel toned, transparent to translucent enamels over an engraved gold base — a technique called ‘guilloche’.

Defining Traits of Edwardian Jewellery 

Further defining methods of this era are millegraining and fret work. Overall pieces are finished with delicate, minute beading making the metal disappear into the design. This millegraining took away the sharp edges, softening the look and emphasising the diamond sparkle. Millegraining also enhanced the knife-edged, open, thin wire work called fret work (like the frets for chords on a guitar neck) that created the airiness to the designs and highlighted the incredible expertise of the craftsman.

After WWI the flowing movement of the graceful Edwardian jewellery eventually blended into, and was then lost to, the geometrical, static, anticlassical, architectural style of the Art Deco era — that caught on like fire. Out with the old, and in with the new. 

Follow your passion for gemmology with one of our in-house diamond grading and gemstone workshops

This article was originally published in the Spring 2019 issue of Gems&Jewellery. Gem-A Members can read the issue online, here

Cover image: The front of a beautiful swan pin, showing the calibré cut emeralds and the typical swinging diamonds, all set in platinum. All images courtesy of Cole Bybee and Lang Antiques

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Explore the History of Garnet in Antique Jewellery

Gems&Jewellery is delighted to welcome jewellery historian and valuer, John Benjamin FGA DGA FIRV as our columnist for 2019. As part of a new Gemstone Conversations series, John explores the history of the use of garnet in antique jewellery and tells us why we should give more credit to this special yet undervalued gemstone.

I have often thought that garnet is a rather underappreciated stone. True, it is extremely common and turns up in everything from ancient gold rings to cheap, modern, mass-produced bijouterie — but this misses the point, which is that the sheer beauty and versatility of garnet meant that right up to the beginning of the 20th century it was consistently one of the most popular of all gemstones used in decorative jewellery.

Historic Uses of Garnet in Jewellery

Garnet was esteemed by the Romans at a time when a vivid gemstone conveyed wealth and status. Fine examples were polished into cabochons or cut into cameos and intaglios depicting classical figures or deities. By the 5th and 6th century garnet was often the stone of choice with small, simple, domed or faceted examples providing a decorative embellishment to Anglo Saxon brooches, pendants and buckles.

Neo Renaissance Gold PendantA Neo-Renaissance gold 'Holbeinesque' pendant mounted with a pyrope garnet cabochon in a champlevé enamelled frame set with chrysolites, circa 1870. Image courtesy of Woolley & Wallis.

Garnet Jewellery of the 17th Century 

No doubt because of its widespread availability it was frequently set into medieval rings and ornaments and by the late 16th and 17th century its sheer abundance and desirability led to it being used throughout Europe in everything from rings and earrings to opulent pendants, usually accompanied by colourful, polychrome enamel and gold mounts.

Many of these Renaissance and later garnets were polished into large and irregular-shaped hollow-back cabochons known as ‘carbuncles’ and were usually rich, purplish-red almandines from India and Ceylon. There are quite a large number of these garnets on display in the incomparable Cheapside Hoard at the Museum of London.

Read more: Garnet for those Born in January

For me, part of the allure of garnet is the broad range of colours available and I have always admired hessonites, not only for their rich, orangey-brown colour but also for their interesting ‘treacle-like’ inclusions. Since garnet is a reasonably hard gemstone it provides an excellent cutting surface, so from the 16th to the 18th century hessonite (known in those days as ‘Jacinth’ or ‘Hyacinth’) was a popular stone for fashioning into cameos or setting into bracelet clasps.

The Golden Age of Garnet Jewellery

Undoubtedly, it was the late 18th and early 19th century when garnet really came into its own. Flat-cut almandines of cushion, pear and circular shape were artfully set into parures comprising a necklace, a pair of bracelets, earrings and a brooch. Foiling the stones and fully enclosing the mounts at the back intensified their glowing appearance, especially when illuminated in candlelight.

Georgian Garnet ParureA Georgian gold and flat-cut almandine garnet parure comprising a necklace, earrings, maltese cross and brooch, circa 1800. Image courtesy of Woolley & Wallis.

The use of garnet in moderately priced jewellery continued through the 19th century reaching a peak of popularity in the 1870s when ‘Holbeinesque’ jewellery – pendants and earrings of a design inspired by the look of the Renaissance – resulted in large pyrope cabochons being set in colourful, champlevé-enamelled frames often accompanied by compatible gems such as diamond or chrysolite. This was the so-called ‘Grand Period’ of jewellery manufacture and the rich, vibrant colour of garnet provided the perfect vehicle for showing off bold and distinctive bracelets, brooches and necklaces.

Read more: Questions to Ask When Buying a Piece of Gemstone Jewellery

Handmade craftsmanship gave way to mechanical, repetitive mass production at the end of the century. Garnet continued to be used in cheap central European jewellery often accompanied by inexpensive colourful gems especially turquoise, pale green beryl and pearls in poor quality, silver gilt settings.

At the same time jewellers in Czechoslovakia (now Czech Republic and Slovakia) began to set clusters of small simply faceted pyropes in base metal thus providing colourful but affordable bangles, brooches and earrings for the mass market. These ‘Bohemian’ garnets are very much of their time and are still very common today.

Bohemian Garnet CrossA 'Bohemian' garnet cross circa 1890. Versatile and inexpensive, these colourful jewels were extremely common at the end of the 19th century. Image courtesy of Woolley & Wallis.

Demantoid Garnet Jewellery 

There was, however, one last moment of glory for garnet. Demantoid, the bright green variety of andradite garnet, had been discovered in the Russian Urals as far back as 1853. Nevertheless, it was not until the 1880s that it started to be set commercially in jewellery and accessories, firstly by Peter Carl Fabergé and subsequently by jewellers in London who obtained supplies from gem merchants such as E W Streeter.

The naturalistic green tones and adamantine lustre of demantoid perfectly conveyed the look of a reptile’s skin or an insect’s body, resulting in a surge of popularity in novelty brooches designed as frogs, lizards and dragonflies. 

Demantoid diamond dragonfly broochA Demantoid garnet and diamond dragonfly brooch, circa 1880. The naturalistic colour of this ever popular variety of andradite garnet resulted in a wide range of novelty insect and reptile brooches appearing on the market at the end of the 19th century. Image courtesy of Woolley & Wallis.

While the more commonplace red varieties of garnet continued to be set in cheap, universally available nine carat gold rings and pendants until the First World War, by the 1920s its use had largely declined and, while it does appear in Post-War ‘Retro’ jewellery and, of course, in modern tsavorite and mandarin garnet rings, the ‘golden years’ of traditional, large scale garnets are now well and truly over. Abundant, often inexpensive and supremely versatile, garnet is surely one of the most underrated of all the better known gemstones. 
If you would like to expand your knowledge on gemstones, find about what Gem-A's Gemmology Foundation and Gemmology Diploma courses have to offer.

This article and images were originally published in the Spring 2019 issue of Gems&Jewellery. Gem-A Members can read the issue here.

Cover Image: Late 18th/early 19th century Neoclassical hessonite cameo ring of the Emperor Tiberius. Images courtesy of Bonhams.

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Gem-A Photographer of the Year Competition Returns for 2019!

We are thrilled to announce that the Gem-A Photographer of the Year competition is back for 2019!

With new rules, a new judging process, and fantastic new prizes, this year’s competition promises to be our biggest and best yet. What’s more, while the competition had traditionally only been open to Gem-A Members and students, we are now happy to accept entries from anyone with an interest in gemmology and a passion for photography.

We are very excited to see what marvels this year’s competition will bring as we have decided to forego categories; instead, we want to see entries that display your own unique interpretation of gemstones, gemmology and the wider trade.

You might decide to share a photograph of a piece of jaw-dropping jewellery, or maybe you have captured the hidden, intricate beauty of a particular gemstone through photomicrography? Or perhaps you have shot a spectacular scene while gemstone mining or trading on a recent trip abroad?

Whatever highlights an unusual or insightful facet of our sector, we want to see it!

2018 Overall Winner - 'Going for the Green': Traders scramble for Myanmar jade at Yangmei's night market in Guangdong Province, China. Image by Richard W. Hughes FGA.

Why Enter?

Win the chance to have your photograph featured in Gems&Jewellery. Winners could be featured on our cover, our Last Impression or our Big Picture feature page.

You can add the accolade of being named Gem-A’s Photographer of the Year to your portfolio.

Entry is free and open to all.

2017 Overall Winner - Dandelion flower in sapphire. Growth blockage with thin film rosette in Sri Lankan sapphire using modified Rheinberg illumination. Field view of 1.34mm. Image by Jonathan Muyal FGA.

The Prize:

The overall winner will be gifted a £300 voucher to spend at Gem-A Instruments and one year’s free Membership of Gem-A.

Two runners up will win a £50 Gem-A Instruments voucher.

All three winning entries will see their photographs published in Gems&Jewellery magazine.

  

2018 Winner - A Persian turquoise dealer presenting a variety of Persian turquoise, temporarily mounted as a ring. Image by Maryam Mastery Salimi.

The competition is open now and we shall be accepting entries until August 30, 2019. The winner will be announced on Gem-A’s Facebook page shortly after the competition has closed.

For the Competition rules and details on how to enter click here. Good luck!

Cover image: 2017 entry - Frog in Amber from the Dominican Republic. Image by Anthony Shih FGA DGA.

Interested in developing your gemmological knowledge? Have a look at our upcoming one-day workshops.

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Buying Guide: Saltwater versus Freshwater Pearls

Treasured the world over for their timeless elegance, lustre and iridescent multi-tonal colours, pearls have been a favourite of high-end jewellers and collectors alike for hundreds of years. 

The majority of gem-quality pearls are produced by bivalve molluscs (an animal whose shell has two hinged parts), but they can also be produced by gastropods (a single shell) which are more rare and may come at a higher price. A pearl is created when an irritant agitates the body of a mollusc and initiates the growth of nacre, a substance that is created by platy crystals of aragonite (a calcium carbonate mineral) held together by an organic compound known as conchiolin.

Well-shaped, naturally occurring specimens can be very rare and highly expensive – in 2017, a natural pearl and diamond drop pendant sold for US$1,452,500 at a Bonhams auction. Cultured saltwater and freshwater pearls are far more abundant and can be cultured to produce excellent lustre in a variety of colours and sizes. But what are the main differences between saltwater and freshwater pearls, and what are the key characteristics that make the highest quality and most desirable specimens?

Saltwater Pearls

Saltwater pearls are produced by oysters found in the sea and generally only a single pearl per shell is found. As natural saltwater pearls are extremely difficult to come across, cultured specimens make up the vast majority on the market. Cultured saltwater pearls are farmed with a bead nucleus made from shells of freshwater molluscs (mussels) as these varieties tend to have thicker shell sections which are ideal for fashioning into a sphere.

3.5-5.9mm Akoya pearls, 3.979cts of diamonds, set in 18ct white gold. From the Yoko London Raindrop Collection. Image courtesy of Yoko London.

Akoya Pearls 

Kokichi Mikimoto perfected the process for culturing pearls in Japan in the 1890s, utilizing Akoya pearl oysters. Akoya pearls are characterised by their very bright lustre and usually white body colour, often enhanced by bleaching. Pink, silver, blue and yellow shades can also occur naturally. Akoya pearls will normally have a diameter of 6-8 millimetres.

Read more: Pearls for Those Born in June 

Grey and black saltwater pearls are highly desirable and have been known to fetch stellar prices at auction. The Cowdray pearl necklace, a string of 42 natural grey saltwater pearls once owned by Viscountess Cowdray, broke the auction record for the sale of a pearl necklace when it sold for US$5.3 million at Sotheby’s Hong Kong in 2015. 

8.5-13.8mm South Sea, Akoya and Tahitian pearls, 18ct white gold clasp. Part of the Yoko London Ombre Collection. Image courtesy of Yoko London.

South Sea Pearls 

South Sea pearls can also be cultured, and although natural specimens would be infinitely more valuable. Cultured South Sea pearls have been known to reach astronomical prices at auction. In 1992 a strand of 23 Australian South Sea pearls sold for $2.3 million at Sotheby’s Geneva. Among the larger of saltwater varieties, they will typically reach 11-14mm in diameter but in some cases they can grow much larger. Part of the desirability of South Sea pearls may be the iridescent gold and silver hues they acquire from the silver-lip and gold-lip molluscs in which they grow.

Tahitian Pearls 

Cultured in a black-lip oyster, Tahitian pearls have a darker nacre with surface iridescence and overtones of peacock, blue, green, purple and gold. Tahitian pearl quality is regulated by the French Polynesian government exerting tight controls to ensure consistent, quality material reaches the market.

12-13mm Tahitian pearl, 0.49ct of diamonds, set in 18ct white gold. From the Yoko London Classic Collection. Image courtesy of Yoko London.

Cortez Pearls 

Originating from rainbow-lipped molluscs found in the Sea of Cortez in Mexico, Cortez Pearls are dark in body colour and display a fabulous rainbow iridescence on the surface. Furthermore, these pearls are somewhat unique as they are the only variety which can show an unusual red fluorescence when exposed to long wave ultra violet light.

Fiji Black Pearls 

Another highly desirable variety of saltwater pearls are Fiji black pearls. Among the rarest types of pearls in the world, they are also a relatively new variety, having first entered the industry in the 1960s. Since then, their introduction by J. Hunter Pearls in 1999 has increased and expanded their market. As a result, we can now see Fiji pearls in a range of vivid colours including gold, peacock, green and chocolate, and although they only have a small yearly output, they command premium prices. 

Freshwater Pearls

Freshwater pearls are grown in rivers and ponds using mussels, and many pearls can be grown within a single shell in a much shorter time that saltwater counterparts. Although freshwater pearls can occur in various colours, white, pink and pastel shades are by far the most common.

There are two ways in which freshwater pearls can be cultured; they can be tissue-nucleated, which means that a small piece of foreign mantle is grafted into the host. This process will usually result in a baroque-shaped pearl.

10-11mm Freshwater pearls, 0.04ct of diamonds, 18ct yellow gold clasp. Part of the Yoko London Classic Collection. Image courtesy of Yoko London.

Cultured freshwater pearls can also be bead-nucleated in the same way as saltwater pearls. Shapes range from round to unique baroques with names like fireball, soufflé and Edison.  However, other shapes are possible, including star, coin and heart. Colour, lustre and size are the most important value factors but they tend to be less lustrous than Akoya pearls.

Considering Value

When considering purchasing freshwater and saltwater pearls, whether natural or cultured, there are five key aesthetic features to take into account in order to make a good investment:

Pearl size

The general rule is the bigger the pearl, the higher the value.

Pearl lustre and orient (shine)

Lustre is a key factor for the majority of cultured pearls and it relates to the amount of light return from the surface of a pearl. Orient is the iridescence of the pearl, a subtle feature created by dispersion of light between platy crystals of aragonite creating different tones.

Pearl colour (shade)

White is a timeless favourite but the value of particular colours is driven by what is popular in fashion at any given time.

Pearl shape

A perfectly spherical shape is always most valuable for pearls.

Pearl surface condition

A near perfect surface condition free from blemishes such as bumps, dimples, scratches and spots will significantly raise the value and market desirability of a freshwater or saltwater pearl.

Read more: Radiocarbon Age Dating on Natural Pearls

While it would always be a very special and rare treat to be able to purchase a set of lustrous, natural round pearls, high quality cultured pearls can make equally, if not more, stunning jewels and a very good investment, particularly when mounted in fine settings from luxury jewellers; exquisite pieces from Harry Winston, Van Cleef & Arpels and Buccellati have recently fetched tens of thousands dollars at auction.

In spite of such awesome prices, the great thing about pearls is that they can be one of the more affordable gemstones to purchase and seem to perennially exude glamour and luxury. If you look out for quality, size, lustre, colour, shape and surface, you are sure to find a fabulous and timeless jewel.

Interested in developing your knowledge about gemstones? Have a look at our upcoming workshops.

Cover Image: 12-13mm South Sea pearls, 0.38ct of diamonds, set in 18ct white gold. Part of the Yoko London Classic Collection. All images courtesy of Yoko London: www.yokolondon.com 

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The History of Queen Victoria's Sapphire and Diamond Coronet

Queen Victoria (1819-1901) famously shared a love of fine jewels and coloured gemstones with her beloved husband, Prince Albert. In fact, one of her most prized possessions - a sapphire and diamond coronet - was designed and commissioned by her husband in 1840. Here, we delve into the story behind this beautiful piece of history.

It is perhaps fated that Queen Victoria’s sapphire and diamond coronet found its permanent home at London's Victoria & Albert Museum in 2019, not least because this year marks the 200th anniversary of the births of both Queen Victoria and Prince Albert. Now, housed within its own cylindrical display cabinet at the heart of the refurbished William and Judith Bollinger Gallery, Queen Victoria’s sapphire and diamond coronet is once again the star of the show. 

The coronet was first acquired by the museum in 2017 and is considered one of Queen Victoria’s most important jewels. It was lovingly designed by her husband, Prince Albert, in 1840 (the royal couple’s wedding year) and was made by jeweller Joseph Kitching.

The coronet is mounted with diamonds set in silver, with 11 step-cut sapphires of octagonal and calf’s head shape, set in gold. The piece was designed to match a sapphire and diamond brooch that Albert gave to Victoria the day before their wedding, perhaps kick-starting the Queen’s love of parures.

In fact, in the same year, she purchased a pair of diamond and sapphire earrings, a brooch and a bracelet of sapphires and diamonds, which suggests she was building a rather impressive matching set!

Read more: What Factors Influence Sapphire Prices?

The design of the coronet was based on the Saxon Rautenkranz – acknowledged as Prince Albert’s coat of arms – although the gemstones are believed to have come from jewellery previously given to Victoria by King William IV and Queen Adelaide.

Prince Albert took a keen interest in Victoria’s jewellery, with one of the Queen’s diary entries from February 1843 stating: “We were very busy looking over various pieces of old jewellery of mine, settling to have some reset, in order to add to my fine ‘parures’. Albert has such taste and arranges everything for me about my jewels.”

 

Queen Victoria, François Forster (1790-1872), Paris, 1846, after Franz Xaver Winterhalter (1805-73). Engraving on paper. © Victoria and Albert Museum, London.

Soon, the coronet was immortalised in influential early paintings of Victoria, including the 1842 official portrait by Franz Xaver Winterhalter, making the sparkling jewel a recognisable symbol of her power and status.

Prior to the untimely death of Prince Albert, Queen Victoria famously had a great love of colourful gemstones and transformable pieces that could be worn in multiple ways. In 1866, she wore the coronet in place of the heavy state crown at the first Opening of Parliament she attended after Albert’s death (perhaps signalling that the piece gave her confidence).

Speaking on the introduction of the coronet to the V&A, senior curator Richard Edgcumbe said: “Queen Victoria’s sapphire and diamond coronet is one of the great jewels of her reign. Designed by Prince Albert, it is an iconic symbol of their love, worn by Victoria as young queen and as widow. We are entirely indebted to William and Judith Bollinger and their sons for the gift of this masterpiece of the jeweller’s art, which is so intimately associated with Victoria and Albert that it will become part of the identity of the V&A.

"Together with an array of eighty new acquisitions and loans made possible by the generosity of many supporters, the display of the coronet inaugurates the next phase in the life of a much-loved gallery.”

All images credit to Jewellery, Rooms 91-93, The William and Judith Bollinger Gallery at the Victoria and Albert Museum (V&A).

This article was originally published in the Summer 2019 issue of Gems&Jewellery.

Thinking of enhancing your knowledge of diamonds? Take a look at our Diamond Diploma and Diamond Grading and Identification course.

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ロンドン塔の収蔵品「クラウン・ジュエル」

 

アンドリュー・フェローズ FGA DGAが、世界で最も有名な宝石コレクションである「クラウン・ジュエル」にまつわる神話や伝説を見ていきます.

有名なクラウン・ジュエルCrown Jewels が収められているロンドン塔の基礎は、征服王ウィリアムによって1066年に築かれました。そして、代々の君主たちによって改造や修復が重ねられ、13世紀後半までには今日見られる大体のレイアウトが確立しました。ヨーロッパで唯一現存するクラウン・ジュエルは141以上の宝物で構成され、何百年もの間ロンドン塔の中で安全に保存されてきました。これらは毎年、多くの観光客を惹きつけています

このコレクションには、単に宝物の美しさを堪能する価値があるだけでなく、宝石類の背後にある魅惑的な物語と歴史について学ぶ価値もあります。

帝国王冠(インペリアル・ステート・クラウン)

帝国王冠(インペリアル・ステート・クラウン)―コレクションにおける最も有名な王位の象徴― は、即位式終了後に君主が頭上に戴くもので、議会の開会の際にも使われます。王冠には、このような重要な行事に際して、王冠自体と同じくらい凝った専用の儀式用馬車が用意されています。王冠は実に3.17kgもの重量があり、短い間のみかぶることができます。

ジョージ4世が1821年に戴冠した際、王冠の重さが理由で歯痛になったという逸話があります!王冠にはロイヤル・コレクションにおいて重要な宝石がいくつか使われており、その多くには非常に面白い物語があります。

黒太子のルビー

多くのジェモロジストがよく知っている物語の一つとして、黒太子のルビーが挙げられます。これは、最も美しい宝石であると同時に最も不吉な石といわれています。そればかりか、完全に誤った名がつけられています。ルビーと呼ばれていますが、実際は非常に大きな宝石品質のレッド・スピネルです。この宝石は、デューク・オブ・コーンウォール、プリンス・オブ・アキテーヌと呼ばれ、「黒太子」とも称される14世紀のプリンス・オブ・ウェールズであったエドワード皇太子(エドワード・オブ・ウッドストック)に贈られました。

The Imperial State Crown. Copyright Cyril Davenport. Tower of London
帝国王冠(インペリアル・ステート・クラウン). Copyright Cyril Davenport

王冠の前部のカリナンIIより上にあるクロスパティー(末広十字)についているこのスピネルには、黒い、血の歴史があります。14世紀に書かれた最初の記録によると、ムーア人の皇太子であったアブー・サイードがこの石を所有し、ペドロ残酷王が征服していた軍隊に引き渡そうとしますが、彼は休戦旗の下で待ち伏せされ、奪われたこの大きなスピネルで処刑されました。これがまさに血の軌跡の始まりです。その後、ペドロは軍事援助のための頭金としてこの石をエドワード皇太子に差し出しました。支払いの残りは宝物と宝石から成ると思われていましたが、決して支払われることはありませんでした。そして、結局、ペドロは彼の異母兄弟に待ち伏せられて刺し殺されました。

後にこの石は、1415年のアジャンクールの戦いで、ヘンリー5世のヘルメット(兜)につけられ、言い伝えによると石が彼の命を救ったとされています。斧で彼の頭が強打されたときそのヘルメットは破壊されたものの、彼を死に至らしめることはありませんでした。「ルビー」は粉砕されたヘルメットから取り出され、ヘンリー5世が亡くなるまで手元に置かれました。残念なことに、リチャード3世に関しては同じことは起きませんでした。彼もまた1485年のボズワース・フィールドの戦いのとき、「ルビー」をヘルメットにつけていました。おそらく、彼は石が身を守ってくれる、運をもたらすと思っていました。しかし、悲しいことに、彼は戦場で死んでしまいます。この同じ「ルビー」は後にチャールズ1世によって売却されるまで、ヘンリー6世とエドワード4世の王冠、ヘンリー8世(彼は石をを襟に着けていた)に使われました。そしてこの石は王室に戻りチャールズ2世の王冠に用いられ、その後ジョージ4世の即位式で使われました

聖エドワードのサファイア

また、帝国王冠の上部の十字架には、サファイアがセットされています。伝説によれば、このサファイアは、かつて証聖王エドワード(信仰のあつい英国王)の即位の指輪(コロネーション・リング)につけられていました。ある夜、エドワードがウェストミンスター寺院の前を通ると、一人の乞食に遭遇しました。彼は持っていたすべてのお金をすでに寄付してしまっていたので、深く考えずにその乞食にサファイアのついた指輪を与えました。

数年後、2人のイングランド人が聖地巡礼中、嵐に襲われました。その時1人の老人が彼らに近づいてきました。そして、2人の男がイングランド人であること、エドワードが今も国王であることを聞き、その老人は彼らに嵐の避難所を提供しました。翌朝、彼らが出発する際、老人は、自分が福音記者ヨハネであることを明かし、数年前にエドワード国王が指輪をくれたことを話しました。老人は親切のお礼に6か月後に天国で会うでしょうというメッセージとともに指輪を国王に返してほしいと彼らに託しました。2人の男がイングランドに帰国すると、エドワード国王に指輪とメッセージを渡しました。そして、国王は直ちに自らの死に備えました。国王は6ヵ月後に亡くなり、指輪をはめて埋葬されました。不思議なことに、事実、墓が12世紀に再び開けられたとき、その指輪は完全に保存された遺体の上で見つかりました。

Tower of London at night. Copyright Kjetil Bjørnsrud. Tower of London
夜のロンドン塔. Copyright Kjetil Bjørnsrud

これらの物語の一部は単に伝説であって、本当かもしれませんし、そうではないかもしれません。しかし事実として、クラウン・ジュエルの中で最も有名で世界で一番大きなダイヤモンドは、コー・イ・ヌールとカリナンであると言えるでしょう。

カリナン・ダイヤモンド

カリナンは、1905年1月26日の午後に南アフリカのプレミア鉱山で、鉱山本部長であったキャプテン・フレデリック・ウェルズによって発見されました。それは3106ctの重さ、3 7/8×2 1/4×2 5/8インチで、その日までに発見された他のどのダイヤモンドよりも2倍以上の大きさであったため、当初、彼はこの石がダイヤモンドであることに疑いをもちました。その後、石はトランスバール政府に£150,000で売却されました。そして、2年後には未カットの状態でエドワード7世の66回目の誕生日に贈られました。その規模や価値はわからなかったものの、石のカットは、大きな石をカットする経験のあるアムステルダムのI. J.アッシャー・アンド・カンパニーに依頼され、3ヵ月検討した後、ようやくカリナンはカットされることになりました。

当時、ダイヤモンドを分割する唯一の方法は劈開を利用することでした。―ダイヤモンドの弱い方向に沿って割れるように正確な方向を「打つ」方法ですが、粉砕することを避けるために、慎重に行わなければなりませんでした。そして石を慎重に劈開させた結果、9個の大きな「かけら」と96個の破片になりました。全てのカット工程が終わった後に残った重量は合計1063ctでした。

カリナンⅠ~カリナンⅨと名付けられた9個の大きな石はすべて、ロイヤル・コレクションに属しています。大きい石は、他のジュエリーにも使用できるようにセッティングが作られます。別名「アフリカの星」と呼ばれるカリナンⅠは王笏に用いられ、503ct以上の重さがあります。この石は世界最大の無色のペア・シェイプ・ダイヤモンドです。カリナン II(「アフリカの小さい星」)は、世界最大のクッション・シェイプ・ダイヤモンドで、317ctの重さがあり、帝国王冠の正面にセットされています。この石にもセッティングには2つのプラチナの輪がついており、取り外しが可能です。そしてブローチやペンダントとして単独で着けられ、またカリナン Iと共に着用することもできます。

コー・イ・ヌール・ダイヤモンド

2番目に注目に値するダイヤモンドは、皇太后の王冠にあります。これはコー・イ・ヌールと呼ばれており、「光の山」という意味をもちます。この印象的なダイヤモンドの現在の重量は105.6ctで、もともと186ctあったこの石は、1852年にヴィクトリア女王のためにリカットされました。

この石は、身に着ける女性に幸運をもたらすという伝説があります。しかし、男性には不幸がふりかかります!1739年にペルシャのナーディル・シャーがムガルを征服しましたが、統治者がもつとされるこの珍しい伝説のダイヤモンドを見つけることができませんでした。宮廷の1人が彼にこの石の在り処を話すと、シャーは祝賀会を開き、永遠の友好のしるしとして征服された指導者たちとターバンを交換することを申し出ました。なぜなら、これがコー・イ・ヌールの隠されている場所であったからです。

ダイヤモンドはその後、数十年の間しばしば持ち主が変わりました。1850年までに、コー・イ・ヌールはイングランドへ伝わり、ヴィクトリア女王へわたり、そして現在に至ります。

クラウン・ジュエルは素晴らしいイギリスの歴史がある一方で、伝説に包まれた装飾品以上の存在です。ここには多くの物語と歴史があり、訪れる人々がそれを発見するのを待っています。宝石学的、歴史的な視点でこの宝物を鑑賞するのも良いですし、決して買うことができない宝石を見るのも感動的です。ロンドンで有意義な一日を過ごす方法として、クラウン・ジュエルはお勧めです■ 

この記事はGem-Aの機関誌Gems&Jewellery Sept/Oct 2016 / Volume 25 / No. 5 pp. 14-15から引用したものです。

表紙はカリナン・ダイヤモンドの原石から分割されたカット前の9つの石を大きいものから順に並べたもの。


The Fascinating History of Antique Turquoise Jewellery

The Fascinating History of Antique Turquoise Jewellery

In his third Gemstone Conversations column for Gems&Jewellery, Jewellery Historian and Valuer John Benjamin FGA DGA FIRV explores the fascinating history of turquoise and its use in jewellery design from the Shahs of Persia to the Art Deco design movement.

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Birthstone Guide: Turquoise For Those Born In December

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Beautiful blue turquoise is one of three birthstones for the month of December (in addition to zircon and tanzanite). It is enriched with real cultural significance that can be traced back thousands of years. Here, we explore the blue shades of turquoise and explain what makes this gemstone so special...

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Highlights of Gem-A Conference 2019

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The Gem-A Conference is always the highlight of our gemmological calendar! If you didn’t manage to make it, we’ve put together a few of the highlights from this year’s event to fill you in on what you missed, and whet your appetite for Gem-A Conference 2020!

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The Famous Diamond Collection of Cardinal Mazarin (1602-1661)

Having successfully completed her Gemmology Diploma and Diamond Diploma, Charlotte Pittel FGA DGA shares an abridged version of her excellent project on Cardinal Jules Mazarin and his legendary love of diamonds.

The Mazarin diamonds were a collection of 18 diamonds left to Louis XIV and the French Crown Jewels by Cardinal Jules Mazarin. Discovering the story of this group of diamonds, the man who collected them and what happened to them is like an incredible work of fiction.

The Life of Cardinal Mazarin

Born Giulio Raimondo Mazzarino on July 14, 1602 to a minor Italian noble family, Mazarin was a man of many interests and talents. His early education was at Jesuit school in Rome before studying law in Madrid. On his return to Rome around 1622 he attended the University of Rome La Sapienza, and following a spiritual awakening he entered the pontifical army.

In 1628 he joined the diplomatic services for the Holy See and became involved in Italian politics whilst working alongside the Cardinals Sachetti and Barberini. His subtlety, patience and hard work were recognised and in 1630, during the war between France and Spain over Mantua, he was sent to negotiate with Cardinal Richelieu.

A bust of Cardinal Jules Mazarin in Paris. Photograph by PlanetKorriban on Flickr (Creative Commons).

Richelieu, impressed with the young man, invited him to Paris where he soon became a confidant and advisor to the Cardinal, joining the court of Louis XIII and Queen Anne d’Autriche. After taking French citizenship he became known as Jules Mazarin and in 1641, was promoted to the rank of Cardinal.

Following Richelieu’s death in 1642, Mazarin succeeded him as the Chief Minister of France and, after the death of Louis XIII in 1643, assisted the Regent Queen Anne in governing France on behalf of her then child son, Louis XIV.

Mazarin was a keen student of the arts, but diamonds were his first love. His collection contained the most beautiful examples, many of them sourced from other European royal families, his preferred jewellers of the time including Lescot, Gabouri, Lopés, and almost certainly from renowned traveller Jean Baptiste Tavernier (1605-1689), who would also supply King Louis XIV.

The 18 Mazarin Diamonds. Illustration inspired by the work of author, Bernard Morel. Image: Charlotte Pittel.

Following his death, Mazarin made generous donations to hospitals, hostels and the arts, and bequeathed his extensive collections of jewellery and gems. Queen Anne received the Rose d’Angleterre (a large round diamond of approximately 14 carats) and a perfect cabochon ruby in a ring.

The Duc d’Orléans received 31 emeralds, while Queen Marie-Thérese was bequeathed a cluster of diamonds. Among his more noteworthy instructions, however, was his wish that a collection of 18 diamonds be given to the King and the Crown of France, on condition that they carry the name Mazarin.

The Famous Mazarin Diamonds

Mazarin assembled this rare and beautiful collection of 18 stones towards the end of his life. Only three of these stones are named: the Sancy, the Mirror of Portugal and the Grand Mazarin. Sadly, due to the tumultuous nature of 18th century French history, many of the 18 stones have disappeared.

An impression of the Mirror of Great Britain, as seen affixed to King James I's hat in a portrait that is housed in the Scottish National Portrait Gallery. Image: Charlotte Pittel.

The Mazarin I — the Sancy Diamond

It is believed that the 106 (old) carat Sancy formed part of the collection of Charles the Bold, Duke of Burgundy. Following his death it disappeared for over 20 years, finally reappearing in Germany in the hands of a merchant banker named Jacob Fugger. He planned to sell the diamond to the King of Portugal, Don Manuel I, and re-cut it into the pear shape we see today.

During a period of huge political upheaval and conflict between England, France, Spain and Portugal, the diamond would finally end up in the collection (and take the name) of Nicholas de Harley, Seigneur de Sancy and Baron de Maule (1546-1629).

De Sancy was made Superintendent of France by Henry IV and pledged his diamonds to raise money for the crown. In 1596, however, he negotiated the sale of the stone to James I of England, who set the Sancy as a pendant into the jewel known as the Mirror of Great Britain.

Read more: Diamond for Those Born in April

James’s successor Charles I sold off precious stones to raise funds for the Royalist cause and, in 1644, sent his consort Queen Henrietta Maria to France to secure supplies and munitions. She borrowed enormous sums from the Duke of Epernon and pledged the Sancy as collateral. In 1649, when Charles I was beheaded, the Queen was exiled. The Sancy diamond was claimed by the Duke and subsequently sold to Cardinal Mazarin.

The Sancy then became part of the French Crown jewels and was mounted in Louis XV’s coronation crown in 1722. Today, the Sancy is on display at the Louvre Museum in Paris.

John de Critz's 1604 portrait of James I shows the King wearing the legendary 'Mirror of Great Britain' jewel. Image: Public Domain.

The Mazarin II Diamond

Author Bernard Morel suggests that this stone could well be the Pinder diamond, based on a 17th century description and drawings made by Thomas Cletscher. Sir Paul Pinder was a businessman and diplomat and, in 1611, James I made him an ambassador to Turkey where he managed to acquire some exceptional jewels, including the Pindar.

Called at this time the Great Diamond, it was acquired by Charles I in 1625 for 18,000 livres but not paid for. It is likely that this is one of the stones pledged by Queen Henrietta Maria in 1646 and then acquired by Mazarin, becoming known as the Second Mazarin.

It was included in a diamond chain worn by Louis XIV, before being re-cut and set into the centre of the Order of the Golden Fleece made by Jacquemin for Louis XV. Thereafter it was unset and remained in the collection of Louis XVIII until his death in 1824, at which time it was returned to the Crown collection. Sadly, the stone was stolen during the 1848 revolution.

The Mazarin III — the Mirror of Portugal Diamond

This stone belonged to Dom Antonio, Prior of Crato. After a short period with Elizabeth I and named the Portugal Diamond, it was mounted into a pendant set with a large pearl drop and given to Henrietta Maria on her betrothal to Charles I. It eventually became a part of the Mazarin Collection.

Read more: Questions to Ask When Buying a Piece of Gemstone Jewellery

As was the custom, many of the French crown jewels were in settings that allowed a freedom in how they could be worn. As such, the Mirror of Portugal was set not only in Louis XIV’s diamond chain, but also in a hairpin worn by Queen Marie-Thérèse, which also bore the Grand Mazarin and some substantial pearls.

The Third Mazarin was unfortunately lost to the French Crown jewels when a substantial number of the jewels were sent to Constantinople never to return, including the Mirror of Portugal and many other Mazarins.

The Mazarin IV Diamond

This stone was first referenced in Bernard Morel’s book as being set into a pair of Girandole earrings created for Queen Marie-Thérèse. It is shown sitting as the top button with the Mazarin V as a drop. Its pair uses other diamonds, including the Mazarin VI as the drop.

An illustration of Queen Marie-Thérèse's girandole earrings, inspired by the work of Bernard Morel, containing some of the Mazarin diamonds. These earrings were documented in the 1691 inventory of the French Crown Jewels and were valued at 500,000 livres. Image: Charlotte Pittel.

The Mazarin V and VI Diamonds

Both the Mazarin V and Mazarin VI were pierced at the top, so were perfectly shaped to be worn as drop earrings. Records suggest that both of these stones were cut by Francisco Ghiot of Antwerp: 1632 for Mazarin VI and Mazarin V in 1636. In a later inventory of 1774, they show up possibly as rings.

The Mazarin VII — Le Grand Mazarin Diamond

This legendary coloured diamond was sold at Christies on the November 14, 2017, achieving a price of CHF 14,375,000 (approximately GBP £10,969,567.60). A GIA certificate (No. 5182785154) and classification letter confirms that this historic light pink, old-mine brilliant-cut diamond is a Type IIa and weighs approximately 19.07ct.

Read more: The Geology of Diamonds

This diamond can be traced back to Indian mines near the Golconda trading centre, but quite how it came to Cardinal Mazarin is unknown. Once the diamonds were passed to Louis XIV and the Crown Jewels collection, it is believed that Queen Marie-Thérèse was the first to wear it.

Following her death in 1683, Louis regained the Grand Mazarin and added it to his legendary chain of diamonds. It was listed in the 1691 inventory as sitting at number five on a chain of 45 diamonds, numbered in descending order of size. It was added to the crown of Louis XV, along with the Sancy.

The Mazarin VIII Diamond

One of the few diamonds to survive a significant sale in 1795, this Mazarin stone sat at either position six or seven on Louis XIV’s diamond chain. The standout piece in which it featured, along with the Grand Mazarin, was the Diamond Diadem of Marie-Louise, Empress of the French from 1810 to 1814. A large diamond parure was ordered soon after the wedding of the Emperor and Empress, along with a coronet, a necklace, pair of bracelets, girandole earrings and a belt. There was also an order for a substantial diadem.

An impression of Empress Eugénie's reliquary brooch designed and created by Alfred and Frederic Bapst in 1855. It was sold to the Louvre Museum in Paris in 1887. Image: Charlotte Pittel.

The Mazarin IX Diamond

Originally described as boat-shaped, the term ‘marquise’ was coined during the reign of Louis XV, largely due to a rumour that it matched the lip shape of his mistress, Madame Marquise de Pompadour. This diamond was set as the eighth button on one of Louis XIV’s justacorps (an open-fitted coat).

The Mazarin X — XVI Diamonds

Along with others, these diamonds were also included in the diamond chain belonging to Louis XIV and also in the coronation crown of Louis XV. The Mazarin XII was described as having a red colouration, probably due to the reddish flaw in its girdle.

The Mazarin XVII-XVIII Diamonds

The last two stones of the collection - XVII and XVIII - were virtually identical, with XVIII slightly larger. It seems that these stones were kept as a pair and used as buttons on a coat belonging to Louis XIV. They are most famed for being part of Empress Eugénie's reliquary brooch of 1855, now part of the collection at the Louvre.

The Mazarin Cut

It should be noted that none of the 18 diamonds that Cardinal Mazarin bequeathed to Louis XIV were cut in the ‘Mazarin cut’. Instead, the cuts were as follows:

  1. Pear-shape double rose cuts — I (Sancy), V and VI
  2. Rectangular table cuts — II (Mirror of Portugal), III, IV
  3. Square table cuts — VII (Grand Mazarin), VIII, X, XI, XII, XIII, XV, XVI
  4. Heart-shape flat rose cuts — XVII, XVIII
  5. Marquise — IX

The fashioning of diamonds in 17th century Europe was undeveloped. Until the 1400s the natural form of the diamond was used, so an octahedral crystal or other rough was refined and set (known as the ‘point cut’). The table cut was first seen around 1477, marking the first true cut where the octahedron crystal had its top flattened by grinding and sometimes a culet added to the lower point. Varieties of the table cut are the thick table cut, the mirror cut, the tablet and the lasque cut.

A representation of the Mazarin Cut, inspired by the drawings and insights of Eric Bruton and Herbert Tillander. Image: Charlotte Pittel.

After the table cut followed rose-cut stones; a flat backed stone with a domed front. There were a variety of rose-cut styles in use at the beginning of the 15th century and it was considered the most appropriate cut for a flatter, thinner stone. Early brilliant cuts were first seen in the mid- 1600s, leading us back to the diamond-loving Cardinal Mazarin.

Single-cut or eight-cut diamonds had eight facets on the table and eight facets on the pavilion plus a culet. These then evolved into the double, cut with 16 facets on the table and 16 facets on the pavilion plus a culet.

It was in the mid-17th century that the Mazarin cut appeared, cushion-shaped with 34 facets in total: 17 facets on the table and 17 facets on the pavilion, including the culet, plus a girdle. This design of facets greatly increased the diamond’s reflective properties and it showed more fire and brilliance.

Although Mazarin was a devoted diamond collector, it is unlikely that he actually invented the Mazarin cut. However, he was a definite forerunner in the rise of popularity for this style of cutting and it is most likely that the cut was named after him as a tribute.

The complete version of this project, including references, appendices and a bibliography are available upon request. All images and illustrations are supplied by the author unless otherwise stated.

This article was originally published in the Spring 2019 issue of Gems&Jewellery.

Do you share Mazarin's passion for diamonds? Enhance your knowledge with our Diamond Diploma.

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Gem-A's Gem Empathy Competition 2019 Now Open for Entries

Gem-A is delighted to announce the return of the Gem Empathy Award for 2019 - a jewellery design competition hosted in collaboration with International Jewellery London. 

For many years the Gem Empathy Award has given exhibitors at International Jewellery London (IJL) the chance to win a gemstone and bring a unique and inspiring jewellery design to life. Now, for the very first time, the Gem Empathy competition is open to IJL exhibitors AND registered IJL 2019 visitors. 

To get involved with this fantastic competition and win some great prizes, continue reading below. We look forward to seeing a whole host of creative entries. 

The Gem Empathy Award Gemstone 2019

The challenge is simple: design an inspiring piece of jewellery that incorporates a special gemstone selected by Gem-A. The designer or brand with the best design will win the gemstone to transform their hand-drawn sketch or CAD design into a three-dimensional, finished piece. 

Read more: Turkish Designer Özlem Tuna Named Gem-A's Gem Empathy Award Winner at IJL 2017

So, what is the gemstone of 2019? See below for the essential facts...

+ 12.9 carat precious coral cabochon

+ Sourced from sustainable coral supplier, Enzo Liverino 1894

+ Dimensions - L: 22.8mm W: 10.09mm H: 6.9mm

+ Hardness 3 - 4

The 12.9 carat precious coral cabochon that will inspire designers in this year’s Gem Empathy competition, in collaboration with IJL 2019.

 

Why Coral?

The Pantone Colour of the Year is coral, which means it is the perfect time to shine a spotlight on this beautiful stone. Moreover, with pollution, climate change, trawling and overfishing leading to vast levels of coral bleaching, stock depletion and damage to sea life in recent years, it is more important than ever to advocate for sustainable sourcing of precious coral which live in a different ecosystem than the endangered reef corals. This is why we have chosen a stone from Enzo Liverino 1894.

With a history of coral work going back over 120 years, Enzo Liverino 1894 is a long-established family business based in Torre del Greco, Italy. Through constantly developing techniques, and a commitment to creative and original design, Enzo Liverino 1894 has become internationally renowned as a coral jeweller of exceptional quality.

Enzo Liverino, the company’s director, is also president of the CIBJO Coral Commission, which aims to ensure that all precious coral is harvested in a responsible way and with sensitivity to sea life in order to ensure sustainability.

Note the white lengthwise interior that is an identifying feature of Pleurocorallium elatius.

The particular breed of coral we have chosen is known as Pleurocorallium elatius (Ridley, 1882), a species of precious coral within the Corallidae family that originates from Japan and Taiwan, and tends to grow in depths of 150-350 metres.

Read more: Breaking Down the Misunderstandings about Precious Coral

The Pleurocorallium elatius grows in a fan shape and is the largest type of precious coral; an average colony will reach, in average, a height of 35cm, have a trunk diameter of 25mm and weigh approximately 500g. This variety of coral typically appears in bright red, salmon, orange and flesh-coloured tones, known in the trade as Cerasuolo, Momo or Satsuma, and can be uniquely identified by its white lengthwise interior, usually visible at the base of the cabochon.

How to Enter the Gem Empathy Competition 2019

Send your design (hand drawn or CAD image) along with an accompanying paragraph describing the materials used and the inspiration behind the piece to events@gem-a.com before 12 August 2019.

Our judging panel, which includes the Editor of Retail Jeweller Ruth Faulkner, will choose the winner to be presented on the Gem-A booth at IJL on September 1 2019. The winner must be present at the show on Sunday.

The Prize

+ The winner will receive the stone

+ A press release from Gem-A announcing the Gem Empathy Award winning designer

+ An article in Gems&Jewellery magazine

+  A voucher to put towards the construction of the piece

The Judging Process

+ The judging panel is made up of three industry experts from the jewellery industry and Gem-A. They will judge the designs based on the evaluation criteria below:

+ Relationship between stone and design

+ Practicality of design

+ Style and beauty

Judging procedures

All designs will be reviewed independently and anonymously by each judge. If the judges do not feel that the design can be considered for the award the judge will clearly mark this on the judging form with a No. Any designs that receive a No from ALL judges will be eliminated from the competition.

Read more: Gem Empathy Returns with a Bolivian Ametrine for IJL 2018

The remaining entries will be reviewed by the judges using a points system. Each design will be awarded points between 1 –10 based on the evaluation criteria. The design with the highest score will be the winner of the Gem Empathy Award, announced at IJL and crowned on the Gem-A booth on the first day of the show.

Gem Empathy Award winner Ariel Tivon, of Tivon Fine Jewellery, is presented with his prize at IJL 2018 alongside Gem-A CEO Alan Hart.

We look forward to seeing your designs! Good luck. 

Cover image: A profile view of this year's prize stone, a 12.9 carat precious coral cabochon harvested in Japan and fashioned in Torre del Greco, Italy by Enzo Liverino 1894.

Interested in enhancing your gemmological knowledge? Take a look at our upcoming Gem-A Workshops.

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オパールの価値をどう評価するか? 初心者のための価格ガイド

 

かつて、オパールは「縁起が悪い」ことで知られていましたが、近年はジュエリーの中でも需要の多い宝石の1つとなりました。しかし、あるオパールが数千ポンドの価値がある一方で、他のオパールはほんの数ポンドあるいは数ペンスにしかならないのはなぜでしょうか?ここでは、Gem-A Instrumentsのマネージャー、サマンサ・ロイド FGA EGが、オパールの価値を決める要因と、素晴らしい石と平均的な石とを識別するための簡単かつ必須な情報を提供します。

オパールの色

オパールは規則正しく並んだ珪酸球の集合体で格子状の構造をもっています。この珪酸球どうしの間には、シリカ溶液が含まれています。光が珪酸球を通り抜けてシリカ溶液に当たると、その光は回析し、さまざまな虹色の色調が生じます。

遊色は珪酸球のサイズによって左右されます。例えば、球が小さいと青系の色が見え、大きいと橙色と赤色が現れます。格子状の構造が均一であればあるほど、色は濃く見えます。

オーストラリア・オパール。

オパールの種類

一般的に最もよく知られているのは、採掘されたオパールの大部分を占めるライト・オパールでしょう。下地の色は白色から乳白色や明るい灰色で、上部にはさまざまな度合いの遊色が見られます。

オパール本体が透明の場合 ―ライト・クリスタル・オパールとも呼ばれる― 色斑は表面より下の方に見られます。このような石は非常に高い価格になります。暗い地色をもつ ―時に色の輝きを強める― ブラックあるいはダーク・オパールもまたよく知られています。これは、最も稀少で最も価値あるオパールの変種です。

価値の要因

オパールには価値を変える要因がいくつかあります。既に述べたように、ブラック・オパールはライト・オパールに比べて高値が付きます(特にインクのような黒色の地色のものは高いです)。しかし、中程度のブラック・オパールと比較した場合には、素晴らしい品質のライト・オパールの方が高価になることもあります。 

オパールの価値について考えるときは他の要素が平均的であっても、石の明るさと輝きが特に重要です。したがって、多くの色が見られる石でも輝きが鈍いものは、輝きの良い石と同じ価値にならないことがあります。 

オーストラリア・オパール2。
オーストラリア・オパール2。

透明度についてはすでに少し触れましたが、これも重要な価値の要因です。ライト・オパールが透明で鮮やかな色を示すクリスタル・オパールであればさらに魅力的で好まれます。  

次に、価値を考える上でより複雑なのは色についてです。オパールの「主となる色」はその価値も影響を及ぼします。赤色は最も高値がつき、続いて値段が高い順に橙色、黄色、緑色、青色、インディゴ、菫色となります。しかし先に述べたように、青緑色の輝く石は鈍い輝きの赤色よりも価値があることを覚えておきましょう。

オパールの模様

稀に、オパール内での光の回折によって興味深い模様が生じることがあり、この模様が石の価値を上げます。縞模様、孔雀の羽の形、筆で描いたような幅のある色のきらめきに比べ、「ピンファイア」や小さな点状模様が見られる場合は魅力が劣ります。 

オーストラリア・オパール3。
オーストラリア・オパール3。

エチオピア VS オーストラリア 

一つのオパールが数千ポンドもする一方で、他が数百ポンドかそれ以下なのはなぜかを尋ねられることがあるかもしれません。その答えは、オパールの起源にあります。オーストラリアはオパールの重要な産地で、世界で最も素晴らしい数々の石を産出します。

重要なのは、この地域で産出したオパールは含水量が低いことです。つまり、乾燥の影響を受けにくく「ひび割れ」―石の耐久性に影響を与えるヘアライン・フラクチャー(細い線の割れ)― を起こしにくいことを意味します。

これとは対照的に、エチオピアはオパールの新しい産地です。しかし、一部の石は非常に含水量が高く、ジュエリーに用いるには心もとなく不適切といえます。 

エチオピア・オパール。
エチオピア・オパール。

エチオピア、オーストラリア・オパールの写真撮影は、ハットンガーデンにある宝石のサプライヤー、 Marcus McCallum FGA, のご協力に感謝いたします。

オパールについてさらに知りたい方は、Gem-Aの図書室にAndrew and Damien Cody著「The Opal Story」をお勧めします。

Gem-A会員の方は、ウェブサイトにアクセスしGems&Jewellery Spring 2017 / Volume 26 / No. 1 にて記事全文をご覧いただけます。

表紙はオーストラリア・オパールのサンプル。すべての写真提供:Marcus McCallum.

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Understanding Tanzanite

Delve into the Gem-A Gemstone & Mineral Collection and you will find this fantastic cut tanzanite and rough tanzanite crystal specimen (pictured above). Here, Gem-A gemmology tutor, Charles Bexfield FGA, explores what makes this relatively new gemmological discovery so special. 

Found in 1967 at the foothills of Mount Kilimanjaro, tanzanite is a relatively new stone and is the purplish blue variety of zoisite. Zoisite is a species of gemstones which share the same chemical composition; zoisite’s composition is calcium aluminium silicate with hydroxyl.

Read more: Why Tanzanite is the Birthstone of December

Today, tanzanite can only be found in the Merelani Hills of Tanzania. A year after its initial discovery it was named after the country in which it was found and introduced to the market by Tiffany & Co., who transformed this previously unknown gemstone into a highly fashionable jewel. Testament to this stone’s huge popularity, in 2002 tanzanite became adopted as a new birthstone for December by the American Gem Trade Association (AGTA).

The Natural Availability of Tanzanite

Tanzanite is a relatively abundant gemstone. Based on a study conducted by TanzaniteOne Mining Ltd in 2012, 270 million carats are mined per year, which equates to 54 tonnes. The current projections suggest the mines will continue to produce gem quality material at the same rate for another 23 years, providing they can progressively dig deeper and reach all the potential material remaining.

Zoisite rough crystal and facetted gemstone Tanzanite Gem A Blog GemA HMA pear-cut zoisite alongside a rough zoisite crystal. Image: Gem-A.

Currently, there are four main commercial mines for tanzanite in Tanzania, separated into blocks A, B, C and D. Each block is owned by a different company; the case study above was carried out on block C, which is by far the largest block on the site, being bigger than the other three mines combined.

Tanzanite Colour and Structure

Tanzanite gains its distinctive purplish blue colour from the trace elements of vanadium and chromium present within its structure. Tanzanite shows very strong pleochroism, which is an optical property and a term used by gemmologists to describe different colours seen in the same material when viewed from different directions. The pleochroism in tanzanite is so strong it is visible by just turning the stone and viewing it through different directions without the aid of a dichroscope.

Tanzanite Pleochroism Gem A BlogPleochroism in tanzanite. Image by Pat Daly FGA.

Providing tanzanite has not been heat-treated, it will show three pleochroic colours: red-violet, deep blue and a greenish yellow. However, if heated above circa 400°C to 500°C, the greenish yellow colour is removed or substantially reduced and the bluish colour deepens.

Read more: What Are the Most Important Gemstone Producing Countries?

The vast majority of tanzanite on the market today is heat-treated to enhance its colour and marketability. Indeed, tanzanite has proven to be a favourite of the rich and famous in recent years, with celebrities such as Beyoncé, Sarah Jessica Parker and Penelope Cruz having been pictured wearing the gem. The Duchess of Cambridge has also on many occasions been spotted wearing a matching set of pear-cut tanzanite earrings and necklace. 

A faceted tanzanite displaying the stone’s distinctive purplish blue colour. Image: Gem-A.

Currently there is no known method for creating synthetic tanzanite. But keep an eye out for synthetic forsterite, which can be used as convincing simulant at first glance. Like tanzanite, it is also strongly pleochroic, however the colours seen when viewed in the different directions are vivid blue and purple, which helps to differentiate between the two stones.

The Value of Tanzanite

On average tanzanite is quite an expensive gemstone; specimens weighing one carat or less will reach prices of about £225 to £250 per carat. Most faceted tanzanite seen commercially on the market is below five carats, while faceted stones over 30 carats are more seldom seen.

The average price of good quality, untreated tanzanite over five carats is about £900 to £1,100 per carat, while smaller sizes around two to three carats can achieve prices of between £350 to £580 per carat. With this in mind, prices do vary depending on colour and treatments, as well as on the particular suppliers or retailers from which you choose to purchase.

Read more: What Makes a Gemstone Rare?

Tanzanite crystals are usually prismatic and quite well formed; any crystals over 50 carats are considered large and are usually sold to mineral or crystal collectors rather than being cut. The largest piece of tanzanite rough reported in the press was found in 2005 by TanzaniteOne Mining Ltd, weighing in at 16,839 carats (7.43lbs or 3.37kg) and measuring approximately 21.8cm x 8cm x 7.11cm, making it a hugely impressive specimen. 

 

An example of a large rough tanzanite crystal. Image by Pat Daly FGA.

However, the largest tanzanite ever sold at auction is the 423.56 Namunyak Tanzanite, which was set into an 18-carat white gold necklace accompanied by 53 carats of diamonds by jewellery designer Kat Florence; the piece fetched over $300,000 USD at a charity sale in 2016 to raise funds for victims of the Nepal earthquake in 2015.

Tanzanite Buying Advice

Before purchasing a piece of tanzanite jewellery it is important to bear in mind that tanzanite measures between 6 to 7 on the Mohs scale and therefore is not a particularly hard stone. As such, tanzanite can be more liable to scratches and damage and consequently may not be the most suitable stone for wearing as an everyday ring.

Read more: Questions to Ask When Buying a Piece of Gemstone Jewellery

If you decide to buy a tanzanite use a 10x loupe to examine the cut, clarity and any presence of chips or cracks. It is also advisable to compare a number of stones to gauge the hue and saturation of colour. By taking these short steps you can better ensure that you will walk away with a good quality tanzanite specimen.

Discover more incredible specimens in the Gem-A Gemstone & Mineral Collection, including sugilitestibnite and decorative fossils.

Start your gemmology journey today with the Gem-A Gemmology Foundation course or one of our many Short Courses and Workshops. Contact education@gem-a.com to find out more.

Cover image: Rough and polished tanzanites from the Gem-A Collection, photographed by Henry Mesa. 

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The Gems&Jewellery Autumn 2019 Issue Has Landed!

We are pleased to announce that the Autumn 2019 issue of Gems&Jewellery is now available to Gem-A Members and students in print and online.

Our quarterly magazine includes exciting updates from the world of gemstones and jewellery, as well as interviews and features from industry experts and the latest Gem-A news.

The Autumn issue begins with our CEO Alan Hart looking ahead to some of the most anticipated events in Gem-A’s calendar, including International Jewellery London, the Hong Kong Jewellery & Gem Fair and of course the Gem-A Conference 2019! Turn to page 16 for an exclusive preview of the brilliant line-up of speakers and talks planned for this year’s Conference.

An opal mine in Queensland, Australia. Image: Barbara Kolator.

On page 10 you can read Olga González’ highlights of Las Vegas’ jewellery and gem shows in June, which included Couture, JCK and AGTA GemFair. The shows may have been a departure from the norm, but the jewellery was bigger and better than ever. You can see some sparkling and inspiring examples from Valani Atelier, Lord Jewellery and L. Courteille Créations on pages 10 and 11.

Turn to page 12 to go on a journey through the Australian Outback with Gem-A collection curator, Barbara Kolator FGA DGA EG. Her account includes tales of visiting opal mines, sifting for sapphires and gemstone shopping!

Read more: What Are the Different Types of Opal?

Celebrated gemmologist and author, Renée Newman GG, tells us why we should consider redefining the 4Cs of diamonds and proposes a new system '6Cs and 2Ts' on pages 20-21. Directly following on page 22, we delve into the famous Al Thani Collection of treasures, including the 400 pieces recently sold by Christie's, and turn to jewellery historian Jack Ogden FGA for his expert opinions.  

Moonflower Sanni Falkenberg Gem A Gems Jewellery Autumn 2019 issueSanni Falkenberg's Award-Winning Agate 'Moonflower' Vase. Image: Sanni Falkenberg.

Elsewhere, Brighton-based lapidary artist Sanni Falkenberg takes us through the step-by-step process of creating her agate ‘Moonflower’ vase, which won gold at the Goldsmiths’ Craft & Design Council Awards 2019, while over on page 44, we bring you all the essential information – including the brilliant prizes up for grabs – about this year’s Gem-A Photographer of the Year Competition!

Read more: What Factors Influence Sapphire Prices?

The striking cover photo from this season’s issue features the astounding 'Siren of Serendip' sapphire set in a white gold and diamond necklace. On page 36, Rui Galopim de Carvalho FGA DGA reports on the origins of this 422.66 carat gem and the process of transforming it into a magnificent piece of jewellery.

A Turn of the century gold necklace set with turquoises, turquoise matrix and blister pearls designed by Archibald Knox for Liberty & Co. Image courtesy of Charlotte Glyde at Woolley and Wallis.

Jewellery historian and valuer John Benjamin FGA DGA FIRV brings us the next instalment in his Gemstone Conversations series with an exploration of the various faces of turquoise in jewellery design history, from the courts of the Shahs of Persia to the cutting-edge jewels of the Art Deco era. To round off our issue, we look back on our visit to JCK and AGTA GemFair in Las Vegas and let you know where we are heading next!

If that wasn’t enough, this issue also features articles on jewellery designer Sarah Ho’s new Full Circle Collection; the interesting career and upcoming projects of Belgian jewellery designer Jochen Leën; tortoiseshell trading confusion; a Gem-A student project on ‘The Importance of Jade in the Mughal Court’; and a quick introduction of the Ivory Act.

Gem-A Members and students can access a PDF version of Gems&Jewellery here. Simply access the archive with your log-in details. 

Would you like to receive print editions of Gems&Jewellery and The Journal of Gemmology straight to your door? Become a Gem-A Member today.

Do you have an idea for an upcoming Gems&Jewellery feature? Share your thoughts with our editorial team on editor@gem-a.com.

Cover image: The 422.66 carat Siren of Serendip blue sapphire set in a white gold and diamond necklace by jeweller Ingo Henn. Image courtesy of the Houston Museum of Natural Science.

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アンティークのエドワーディアン・ジュエリーの見分け方

 

歴史家、査定人、アンティーク・コレクターにとって、様々な時代やデザインの流行からジュエリーを見分けることは必要不可欠です。ステラ・ターナー FGA GGが、上品で洗練されたエドワーディアン・ジュエリーの世界を紹介し、この時代に特徴的なモチーフについて解説します。  

短かったエドワード7世の治世(1901~1910年)、宮廷ではエドワード王が好んだスポーツを中心としたライフスタイルとデンマーク出身のアレクサンドラ王妃の存在が、1800年代の終わりの流行に新しい風を吹き込みました。それに伴ってジュエリーのモチーフは変化を遂げました。ダイヤモンドを散りばめ、複雑、優雅で均整の取れたレースのようなデザインが流行し、ネックラインや、裕福なシフォンのガウンと「結い上げた」ヘアー・スタイルを飾るようになりました。繊細なスクロール、葉、リボン、ハート、サークル、揺れる垂れ飾り(あるいは、後述するガーランド)、そしてベールのように軽やかなジュエリーは、洗練された新しいスタイルを称えるものでした。

私にとって、エドワード時代のデザインは「凍った瞬間」のように見えます-渦巻き状の動き、かすかな輝き、ゆるやかなドレープ、スクロール、そして揺れ動き、円を描く-それは、ジュエリーが身に着けられ、再び動く時を待つかのようです。エドワード時代の女性らしさ、流動性、繊細さがデザインによく表れています。この時代のジュエリーは基本的に、蝶番、垂れ飾り、花綱、動きを出す構造、流動性、小さく揺れ動く宝石でできた滴で構成されています。

アレクサンドラ王妃は、着け心地はいまいちでありながらも、ファッション性に富み、装飾を施したプラーク(板)のついた「ドッグ・カラー」ネックレスを好み、黒いベルベットを付けて愛用しました。そして、このスタイルは後に6-16列に並べた真珠へと形を変えました-身に着けるのが難しいものです。ドレスのネックラインが変わると、首周りの装飾品にも変化をもたらしました。例として挙げられるのは、リヴィエール・ネックレス-ミルグレイン(ミル打ち)で縁取られた覆輪留めのダイヤモンドが一周したグラデーションの付いた連-であり、これは二本のブレスレットとして着用されることもあります。

ダイヤモンドに「スペクタクル・セット」を施した最長72インチの長い連のネックレスもあります。これは細いワイヤーでダイヤモンドのガードル部分を巻き、脇についた小さな丸カンを隣の宝石につなぐというシンプルな技法です。またラヴァリエールは、デザインが同じパーツから滴状の飾りが下がるように、装飾を施した細い鎖で繋いだネックレスです。ネグリジェ・ネックレスは、二つの飾りが時折異なる長さのシンプルなチェーンで一つのデザイン・パーツからぶら下がったものです。通常、ペンダント(ぶら下がる部分)には、ダイヤモンドがセットされ、彫刻や次第に先が細くなった飾りがあり、繊細にデザインされたチェーンで繋がれています。

ティアラもまたエドワード時代の興味深いジュエリーです。ティアラに似たバンドーはネックレスやブレスレットにも使用することができます-後部にあるネジ穴またはループは、形を変えることができる融通性を示しています。長い真珠の連を束ね、先端にタッセル(飾り房)の付いたソートワールは、首、腰、ボディス(肩からウエストまで)、腕に巻き付けて装いました。ブレスレットには、一周、または上部半周を対称的に繰り返すデザインが用いられました。新しい流行は、先が細くなるデザインをつけた小さなダイヤモンドや色石のブレスレットで、後ろ側で連結金具を繋いだものでした。リングは中央のダイヤモンドの深さが十分に収まるように幅が広くドーム状になりました。

Edwardian Swan Brooch Back by Lang Antiques Gem A Blog Antique Jewellery Vintage美しい白鳥のピンの裏側。エドワード時代に典型的なカリブレ・カットのエメラルドと「スウィングする」ダイヤモンド。

堅いプラチナまたはプラチナを付けたゴールドは、淡くやわらかい女性らしいファッションの色調によく合いました。プラチナは新しい白い金属で、シルバーとは異なり、肌や衣服を汚すことなく、強度があり、最も重要なダイヤモンドを繊細に留めることができました。当初、プラチナはイエロー・ゴールドに接着されました。この技術は新しく、高価でない、価値が認められていない金属に付加価値をもたらしました。

私が見てきたエドワード時代のダイヤモンド・ジュエリーの大多数は、手作り(カット、切断、引き延ばし、引き絞り、組み立て)の作品です。金属を溶かすのには高温を必要とするため、キャストで作ったものは一般的ではありません。イエロー・ゴールドをベースとしたロウを使用しているのが見えてしまうので、エドワーディアン・ジュエリーは通常少ないパーツで組み立てられています。

金属の継ぎ目に見られる黄色味を帯びたロウは、ホワイト・ゴールドが作られるようになった第二次世界大戦後には、白色に近くなり、姿を消しました。さらに、プラチナは素晴らしい金属で-変色しません-変色が見られる場合には、ゴールド、シルバー、プラチナを混合したロウが用いられています。変色や錆は年月が経つにつれて生じるため、そのジュエリーが古いものであることがわかります。金属の磨きなおしは、時に古いものである証拠を取り除いてしまうことがあります。

当時、南アフリカは大量のダイヤモンドを供給していました。第二次ボーア戦争(1899年10月-1902年5月)はダイヤモンドの価格に影響を及ぼしましたが、需要は伸び続けました。この頃になると、ダイヤモンド用の丸い鋸、正確な角度をつけるための固定したドップ(カットするダイヤモンドを保持する締め金)、ブルーティング用の機械の向上と電気によって、カッティングに要する時間を削減しました。これはまた、より輝くラウンド・ヨーロピアン・カットのダイヤモンドを生むことにもなり、マーキーズやペア・シェイプも入手しやすくなりました。そして、カットの際には重量の保持よりも仕上げたダイヤモンドの美しさに焦点を当てるようになりました。

Edwardian Brooch by Lang Antiques Gem A Blog Antique Jewellery Vintageティアラにもヘア・オーナメントにもなるエドワード時代のピン。

後の時代にはシングル・カットのダイヤモンドが過去のローズ・カットに取って代わります。ダイヤモンドを早くカットできるようになり、煌めく17面をもつシングル・カットは、繊細なジュエリーを上手く引き立てることとなりました。小さなスイス・カットとヨーロピアン・カットのダイヤモンドは時代を見分けるのにも役立ちます。エドワード時代の終わりには、オールド・マイン・カットは無くなりましたが、このカットのダイヤモンドは、今もなお新しいジュエリーに再利用されています。

真珠はダイヤモンドに次ぎ二番目に人気があり、エドワード時代のモノクロのスタイルに合っていました。真珠の優美な光沢は、薄手のファブリックと組み合わせると美しく映えました。ぶら下がった滴状の飾りは、まるで水のようにオープン・ワークのデザインに素晴らしい動きの要素を加えました。天然真珠(この時まさに、養殖真珠はかなりの数が市場に登場するところでした)は稀少であったため、3.5mmのシード・パールまたはそれより小さいものは半分で使えるようにカットされ、金属にセットされました。

インド洋やペルシャ湾の海水産真珠はクリーム色~明るいグレー(洗浄に使用する洗剤でグレーになることがあります)で滑らかな表面であるのに対し、アメリカとスコットランドの淡水真珠は白くしわが寄っています。カットしていない大きい天然真珠は、時にボタン型やオーバル型の形状をしています。真円養殖真珠がエドワーディアン・ジュエリーに見られる場合、この真珠は既に取り換えられたものの可能性があります。サファイア、エメラルド、オパール、ルビー、アメシスト、デマントイド・ガーネット、ムーンストーン、ペリドットといった宝石は、周囲を複数のダイヤモンドで飾ったリングに仕立てます-これは、ヘイロー・リングと呼ばれるものです!カシミール産サファイア、ビルマ産ルビー、ロシア産デマントイド・ガーネット、オーストラリア産ブラック・オパールなど、古いジュエリーから宝物を見つけてみましょう。

Edwardian Oval Diamond Brooch by Lang Antiques Gem A Blog Antique Jewellery Vintageエドワード時代の透かし細工のブローチ

とても小さく(1-2mm)真っ直ぐな面をもつ幾何学的な形状のルビー、サファイア、エメラルド、アメシストは、チャンネル・セッティングに合うようにカットされたもので、このカリブレ・カット石はデザインに沿ってセットしていきます。新しく作られた均一な色の合成サファイアやルビーのカリブレ石はエドワード時代後期のジュエリーに見られます。ブラック・エナメルまたはオニキスは、モーニング(喪)・ジュエリーの時代が終わりを迎え、真っ白な見た目にコントラストを与えるものとして使用されました。

プラチナとダイヤモンドでできた中央の装飾は、淡い色の背景によって強調されます。この背景は彫刻したゴールドの土台に透明から半透明のエナメルを施したもので、「ギヨシェ」という技法です。

他にもこの時代の技法にはミルグレインと透かし細工があります。ジュエリー全体が繊細に仕上がり、微小なビーディング加工により金属がデザインに溶け込みます。このミルグレインは鋭い縁を取り除き、滑らかな見た目を作り、ダイヤモンドのきらめきを強調する効果があります。またミルグレインは、透かし細工(ギター・ネックの弦の格子模様のような)と呼ばれるナイフ・エッジのオープン・ワイヤー・ワークをも引き立てます。この細工はデザインに軽やかさを生み、職人の驚くべき専門的技術が際立つものです。

第二次世界大戦後、上品なエドワーディアン・ジュエリーの流行は、最終的にアール・デコの幾何学的、静的、反古典的、建築的スタイルに融合して消えていきました- このアール・デコ・スタイルは瞬く間に人気を博しました。古いものを捨て、新しいものを取り込んだのです。  

Gem-Aのダイヤモンド・グレーディングと宝石のワークショップに興味がある方は、こちらをご覧ください。

この記事は「Gems&Jewellery」Spring 2019号に掲載されたものです。Gem-A会員の方はこちらのオンラインからもご覧いただけます

表紙の写真:美しい白鳥のピン(正面)。プラチナにセットされたカリブレ・カットのダイヤモンドと「スウィングする」ダイヤモンド。写真提供:Cole Bybee and Lang Antiques。

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Gem-A at International Jewellery London 2019

International Jewellery London is just around the corner and all of us at Gem-A are hugely excited for what promises to be a scintillating showcase of jewellery and gemstones!

If you will be attending IJL 2019, we would like to invite you to join us at Booth F21, where you can meet our team, find out about our courses and try out some practical gemmology with our tutors!

While in recent years we were located in the upstairs section of the show, this year we are positioned at the front of the show (on the right hand side as you walk through the door) in a learning hub alongside the NAJ and The Goldsmiths’ Centre.

Guide to International Jewellery London 2019

Sunday 1 September 2019

Presentation: Gem Empathy Award Winner 2019

Location: Gem-A Booth, F21

The entries have been judged and one lucky IJL exhibitor/visitor will be announced the winner of the Gem Empathy Award 2019 and take home the 12.9 carat precious coral cabochon sourced and cut by Enzo Liverino 1894.

Tuesday 3 September 2019

Seminar: Precious Coral & Sustainability

Location: Catwalk Theatre

Read more: Misunderstandings about Precious Coral

Rui Galopim De Carvalho FGA DGA, Vice-President of the CIBJO Coral Commission, dives into the underwater world of precious coral and addresses some of the misunderstandings around its use in the jewellery industry.

Daily at the Gem-A Booth

Across all three days at IJL 2019 we shall be running in-booth gemmology training sessions at our Practical Gemmology Lab! These fun, 20-minute sessions run by our brilliant team of tutors will help you get to grips with the basics of gemstone identification:

10:30 am:  The Diamond Detective

Learn the basics of separating diamonds from its simulants and synthetics.

12:30 pm: A Gemmologist’s Best Friends

Get the most out of your loupe, lights and the microscope.

2:30 pm: Become a UV Jedi

Master the use of UV to distinguish between similar-looking stones.

4:30 pm: Spot the Difference

Separate blue stones with the use of the dichroscope and Chelsea colour filter.

 

Are you a gem detective? Drop by the booth at any time and test your knowledge! Cast your eye over eight different blue stones and try to identify the gems! If you are new to gemmology you can get some help from our gemmology tutors or use the clues provided.

Exclusive Offers for IJL Visitors

We are pleased to invite you to take advantage of special discounts and offers, exclusively reserved for exhibitors and visitors at IJL, including 15% off Gem-A one-day workshops and our GemBasics course when you book at the show!

What’s more, we are offering two fantastic instrument bundles at a significantly reduced rate – an offer only available at the show and while stocks last! IJL visitors and exhibitors can choose from:

Offer 1: The Filters Bundle

Includes: Chelsea colour filter, dichroscope, flat light and Maglite all for £75 inc. VAT, saving £23.40.

 

Offer 2: The Power Couple

Includes: A desktop microscope plus PhotoAtlas Vol. 3 for £1650 inc. VAT plus free UK shipping, saving £220.

 

We cannot wait to see some of the fascinating presentations lined up for the Inspire Seminar Programme, fresh designs from emerging talent and of course the amazing array of gems and jewellery on display. If you haven’t already, head to the IJL website to register! We look forward to seeing you there!

We have some fantastic guest speaker events planned for October, including a workshop on Organics with Gem-A President, Maggie Campbell Pedersen FGA ABIPP and a workshop on The World of Antique Jewellery with jewellery historian and valuer, John Benjamin FGA DGA FIRV. To book tickets, head to the workshops webpage

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A First Time Visit to International Jewellery London 2019

Gem-A’s communications assistant, Olivia Gillespie, reflects on her first experience at one of the UK’s biggest jewellery trade shows, International Jewellery London.

Having never visited International Jewellery London before, it was difficult to know what to expect! Upon walking through the front door of Olympia London on Sunday, the opening day of the show, I was quite taken aback by the enormity of the venue and the masses of visitors and exhibitors already networking and eyeing the many dazzling jewels on display.

I was also quite surprised by the variety of exhibitors, ranging from jewellers and gem wholesalers, to watch dealers and educational institutions, and by how far some had travelled to be at IJL, with some being based as far afield as Denmark, Hong Kong and Canada. There was a veritable feast of jewels and gems to behold at IJL, but a few remarkable exhibits and events made an especially sparkling impression on me…

 The amethyst 'Victoriana' necklace by Fei Liu Fine Jewellery.

International Jewellery London: Fine Jewellery Design

IJL 2019 had numerous exhibitors showing fine jewellery but I was particularly dazzled by the beautifully elegant statement jewels from Fei Liu Fine Jewellery. Fei Liu was showing his new collection, Victoriana, which is inspired by popular gemstones and stone cuts from the Victorian period, most notably the octagon cut, which featured in an exquisite suite of amethyst jewellery on display.

Two stunning statement rings by Fei Liu Fine Jewellery. Ring 1: 18 carat white gold ring set with a 17.35 carat green tourmaline and surrounded by 1.92 carats of tsavorites and 2.19 carats of baguette-cut diamonds. Ring 2:18 carat rose gold ring with a 9.35 carat garnet, 1.68 carats of diamonds and 4 carats of rutilated quartz.

I was utterly transfixed by two glorious rings on the brand's stand. The first is an 18 carat white gold ring set with a 17.35 carat green tourmaline and surrounded by tsavorites and baguette-cut diamonds, while the second is an 18 carat rose gold ring featuring a 9.35 carat garnet centre stone, flanked by 4 carats of rutilated quartz and bordered by diamonds.

Unusual Gemstones

As a member of the Gem-A family, I always get excited to see unusual coloured gemstones. I was very happy to get the chance to peruse the collection of gemstones exhibited by Ntinga, a London-based fine jewellery brand, which included a brilliant array of interestingly gems, including tanzanite, watermelon tourmaline, ametrine, iolite, indicolite and a fiery orange sunstone.

Sunstone from Ntinga

The IJL Catwalk

I made sure to pay a visit to the first catwalk of the day which showcased stunning jewels for women and men from the show’s exhibitors. It was great to see British gemstones as well as British jewellers on display, as one of the models sported CW Sellors’ silver and jet octopus ring and octopus pendant, bracelet and necklace on the catwalk. The huge Whitby Jet jewels on display at CW Sellors’ stand also caught my eye, especially the somewhat spooky spider necklaces!

 Whitby Jet jewellery from CW Sellors

Gem-A's Gem Empathy Award

The first day of IJL also saw the presentation of the Gem Empathy Award, an annual jewellery design competition run by Gem-A and hosted at IJL. Entrants were asked to conjure a design featuring this year’s prize stone, a 12.9 carat precious coral cabochon sourced from Enzo Liverino 1894.

Read more: Breaking Down the Misunderstandings About Precious Coral

The winner of this year’s award was student designer Bingjie Zhao for her magnificent ring design entitled ‘Trawling’. Like the judges I also adored Bingjie’s original and sophisticated design and look forward to seeing her future creations!

Pearls! Pearls! Pearls!

Another of my personal highlights had to be the amazing variety of pearls and pearl jewellery on display. It seemed like there was an ocean of pearls at the show, with wholesale suppliers such as Raw Pearls selling ropes of an amazing variety of pearls, including freshwater, Akoya, and Tahitian, in a sublime array of colours.

The new collection from Ora Pearls

Positioned near the entrance on the ground floor, it was difficult to walk by without stopping to gawp at Yoko London’s divine fine pearl jewellery. At very much the high end of the market, Yoko London’s jewels ooze luxury and many pieces shimmered and sparkled in diamond and white gold settings.

Read more: Saltwater versus Freshwater Pearls

Another fabulous pearl jeweller exhibiting at IJL was Ora Pearls, who was showing a new collection of jewels with a focus on brilliantly large baroque pearls.

New Designers at International Jewellery London

It was very encouraging to see a spotlight on young and emerging jewellery designers at IJL and to see their fresh and unique creations on display. I also really enjoyed getting to speak to these designers and finding out about the inspirations behind their collections. Eloise Kramer told me about her intention to tell a story through jewellery with her nature-inspired pieces, explaining that her colossal resin and copper peach ring should be worn alongside her insect rings to create a scene of creatures swarming around an irresistible fruit.

Eloise Kramer's 'Peach Ring', made from copper and resin, accompanied by one of her 'Insect' rings.

Isla Gilham of Isla Gilham Jewellery was also attracting a lot of attention with her fantastically fun and colourful ‘Jelly Tot Tiara’, which swapped out gemstones for genuine jellies! Another piece which quite literally made me stop in my tracks was a show-stopping necklace from emerging fine jewellery brand Aureliean, which featured a huge sapphire surrounded by diamonds and smaller sapphires and set in 18 carat gold on a double strand of pearls.

 The 'Jelly Tot Tiara' by Isla Gilham Jewellery

Leading Lights Awards & Celebration

As I visited on the first day I was lucky to have been able to attend the drinks reception and Leading Lights Awards, a new addition to IJL for 2019. I found that the awards were a good way to highlight exceptional work from a range of disciplines within the industry – including jewellers, jewellery education providers and bloggers – and to celebrate the achievements of all exhibitors and everyone working behind the scenes to produce such a showcase of international jewellery.

All in all, I had a fantastic experience at International Jewellery London 2019; the variety of interesting jewels on display was a treat for the eyes and I especially loved having the opportunity to speak to designers about their creations and inspirations. I can’t wait to see what next year brings!

Interested in learning more about gemstones? Check out our upcoming workshops.

Are you ready for the Gem-A Conference 2019? Find out more here.

Cover image: Fei Lui Fine Jewellery's 9.35 carat Garnet Ring in rose gold featuring diamonds and rutilated quartz.

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Gem-A at Hong Kong Jewellery and Gem Fair 2019

Hong Kong Jewellery and Gem Fair is only a few days away and we are getting excited to meet visitors and colleagues from the jewellery and gemstone industries, and of course be dazzled by the many gemmological marvels that will be on show at this world-class event.

We invite you to join us at Booth 3M204 in the Hong Kong Convention & Exhibition Centre from 18-22 September to meet our team, find out about our courses, collect your pre-orders and test your gemmological knowledge with a gem quiz! Although our booth number has changed, we shall be located in the same space as last year (in Hall 3 of the Centre).

We also have an exciting array of additional activities and events planned for our four-day visit to Hong Kong – take a look at our schedule to make sure you don’t miss out!

 

Wednesday 18 September

 

Join us at Booth 3M204!

On the much anticipated opening day of the 2019 show we shall be set up at Booth 3M204, ready and eager to meet you and assist with any questions you may have about becoming a Gem-A student or Member. Please note however that we are not able to carry out membership renewals at any point during the show.

The Gem-A booth at Hong Kong Jewellery and Gem Fair 2018. Look out for our legendary front door at this year's show!

You can also test your gemmological knowledge with our ‘Are You a Gem Detective?’ quiz! Drop by the booth and cast your eye over eight different blue stones and try to identify the gems. If you are new to gemmology you can get some help from our gemmology tutors or use the clues provided.

Read more: Understanding the Value of Sapphires

From Wednesday you can also pick up your pre-orders placed with the Gem-A Shop from our booth at any time during exhibiting hours.

Thursday 19 September

 

Gem-A Meet & Greet

From 11.00am-13.00pm you can meet our CEO, Alan Hart FGA DGA, at the Gem-A Booth and take your photo outside the Gem-A front door!  

Gem-A Gathering

After the show on Thursday 19 September, we shall be holding our third Gem-A Gathering in Hong Kong at the Assaggio Trattoria Italiana in the Hong Kong Arts Centre. Less than a 10-minute walk from the Hong Kong Convention Centre, the Assaggio Trattoria Italiana is a modern Italian restaurant with stunning views over Hong Kong.

We invite you to join us at this relaxed and sociable event, where you will have the opportunity to network and catch up with fellow gemmologists, friends and colleagues from 6.30-8.30pm over drinks and canapés. This is a free event and anyone can attend, but please ensure to register your attendance in advance here.

Friday 20 September

 

Gem Empathy Award: Special Presentation

We would love you to join us at the Gem-A booth at 3.00pm for a celebration of entries from Asia to the 2019 Gem Empathy Award and a special award presentation to one outstanding jewellery design that particularly impressed our judging panel. You can read more about the 2019 Gem Empathy Award and announcement of the overall winner at International Jewellery London 2019 here.

Saturday 21 September

 

Meet your local ATC!

On Saturday we will be joined by representatives from two of our Accredited Teaching Centres (ATCs) in Taiwan. If you are interested in studying one of our courses in Taiwan, this is the perfect opportunity to put any questions you may have to our fantastic ATC tutors.

Read more: Five Things to Consider before Starting the Gem-A Gemmology Foundation Course

From 11.00am-12.30pm Mr Wu Chao Ming will be on the stand ready to answer questions, followed by representatives from Taiwan Gemmological Institute from 3.00-4.30pm.

Sunday 22 September

The Last Day!

We shall be back at Booth 3M204 for the final day of the show. Make sure to make the most of your final chance to meet our team, pick up your pre-orders, find out about our courses and discover how you can get involved with Gem-A!

This year’s show looks set to be packed with a host of seminars, talks and exhibits showcasing some of the world’s most incredible gems and fine jewellery. If you haven’t already, visit the Hong Kong Jewellery and Gem Fair website to book your place for this year’s show. We look forward to seeing you there!

Interested in developing you gemmological knowledge? Take a look at our Gemmology Foundation course.

Do you have a passion for diamonds and want to find out more? Check out our free Introduction to Diamonds webinar scheduled for 10 October 2019.

 

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ヴィクトリア女王のサファイアとダイヤモンドの宝冠にまつわる歴史

 

ヴィクトリア女王(1819-1901)が彼女の最愛の夫であるアルバート公とともに、宝飾品と色石に愛情を注いだことは有名です。実際、彼女が最も大切にした愛蔵品の一つ ― サファイアとダイヤモンドの宝冠 ― は、1840年に彼女の夫がデザインし注文しました。ここでは、この美しい歴史の1ページとなった物語を紹介します。

アルバート公の生誕200周年を迎えた2019年に、ヴィクトリア女王のサファイアとダイヤモンドの宝冠がロンドンのヴィクトリア&アルバート博物館で永住の地を見つけたことは、まさに運命といえるでしょう。現在、この宝冠は、改修後のウィリアム・アンド・ジュディス・ボリンジャー・ギャラリーの中心にある円筒形のキャビネットにディスプレイされ、再び輝きを放っています。

宝冠は2017年に初めてヴィクトリア&アルバート博物館が獲得したもので、ヴィクトリア女王の最も重要な宝石の1つと考えられています。それは1840年(ロイヤル・ウェディングの年)に夫のアルバート公が心を込めてデザインし、宝石商ジョセフ・キッチングが製作しました。

宝冠にはシルバーにセットしたダイヤモンドと、ゴールドにセットした八角形で子牛の頭の形をしたステップ・カットのサファイア11個がマウントされています。これは、アルバートが結婚式の前日にヴィクトリアに贈ったサファイアとダイヤモンドのブローチに合うようにデザインされていました。パリュール(一揃いのジュエリー)を女王が愛したのは、おそらくこれが始まりです。

そして同じ年に、彼女はダイヤモンドとサファイアのイヤリング、ブローチ、ブレスレットを購入しました。このことは、彼女が素晴らしいジュエリー一式をコレクションしていたことを物語っています!

宝冠のデザインは、ザクセンのラウテンクランツ(上部に葉や花冠をあしらった飾り帯)-アルバート公の紋章- に基づいています。使用されている宝石は以前ウィリアム4世とアデレード王妃がヴィクトリアに与えたジュエリーから取られたものと考えられています。

アルバート公はヴィクトリアのジュエリーに強い関心をもっていました。1843年2月の女王の日記にはこう記されています。「私たちは様々な古いジュエリーを調べ、美しい『パリュール』に加えるためにいくつかの宝石をセットしなおすのに大忙しです。アルバートはセンスがあり、私のジュエリーのためにすべてを手配してくれます」

宝冠はすぐに、1842年のフランツ・クサーヴァー・ヴィンターハルターによる公式肖像画をはじめ、ヴィクトリアの初期の重要な絵画に描かれて後世に伝わっています。これらの肖像画によって、きらめく宝石は彼女の権力とステータスの象徴となりました。

アルバート公の早すぎる死の前には、ヴィクトリア女王が様々に形を変えることができる色とりどりの宝石がついたジュエリーを愛用していたことが知られています。アルバート公の死後、1866年に出席した議会の開会で彼女は重い帝国王冠の代わりにこの宝冠をかぶりました(おそらく、これは宝冠が彼女に自信をもたらしたことを示しています)。

ヴィクトリア&アルバート博物館へ宝冠が収蔵されたことに関して、シニア・キュレーターのリチャード・エッジカム氏は次のように話しています。「ヴィクトリア女王のサファイアとダイヤモンドの宝冠は、彼女の治世の重要な宝石の一つです。アルバート公によってデザインされたもので、彼らが育んだ愛の象徴であり、ヴィクトリアは若い女王として、そして未亡人としてかぶりました。ジュエラーによる傑作というこの贈り物は、ウィリアム、ジュディス・ボリンジャー、ならびに彼らの息子たちのおかげです。そして、それは博物館のアイデンティティの一部になるほど、本当の意味でヴィクトリアとアルバートを連想させるものです」

「多くのサポーターのご厚意によって80もの新しい収蔵品を獲得し貸出いただくことが可能となりました。宝冠は、皆さんに愛されているギャラリーの中心で展示され新しい時を迎えます」

すべての写真のクレジット:ヴィクトリア&アルバート・ミュージアム(V&A)のウィリアム・アンド・ジュディス・ボリンガー・ギャラリー、ジュエリー・ルーム 91-93。

この記事は、Gems&Jewellery Summer 2019 に掲載されたものです。

ヴィクトリア女王、フランツ・クサーヴァー・ヴィンターハルター(1805-73)が描いた後、フランシス・フォスター (1790-1872)による彫版、 パリ、 1846年。 紙に彫版印刷 © Victoria and Albert Museum, London.

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Understanding the Cat's Eye Effect in Gemstones

Chatoyancy is the gemmological name given to the curious optical effect in which a band of light is reflected in certain cabochon-cut gemstones, creating an appearance similar to light bouncing off a cat's eye. Gem-A's Collection Curator, Barbara Kolator FGA DGA explains chatoyancy and highlights some of the many gems in which it can occur.

Chatoyancy is the name given to the ‘cat’s eye’ optical phenomenon which can be seen in certain gemstones. The term ‘chatoyancy’, deriving from the French for ‘shining like a cat’s eye’, denotes the effect that occurs when a bright light is shone onto a rounded, reflective surface and causes light to be reflected back in narrow line perpendicular to the observer’s line of sight. This can be seen by looking at a spool of shiny thread or some cabochon-cut gems.

What Causes Chatoyancy?

Chatoyancy occurs when a band of light is reflected from a series of thin inclusions which are parallel to each other (these may be hollow tubes or needle-like crystals of, for example, rutile or haematite).

 In order to display this effect there must be enough fibres oriented in parallel to the base of the stone. The gemstone also has to be cut as a cabochon to provide the necessary rounded surface for the line of light to be seen.

Read more: The Star of India Sapphire

 As the light moves, or the observer’s eye line moves, the line appears to move too, appearing just like the way a cat’s pupil will look under a bright light.

A chrysoberyl cabochon showing a sharp chatoyant effect. Image by Pat Daly, Gem-A.

 The type of line produced will depend on the types of inclusions; the sharpest, finest line is produced in chrysoberyl, which is the only stone which may actually be called ‘cat’s eye’, without a qualifying species name. Such a stone will possess needle-like inclusions which form an effect known as ‘silk’. As a result, a very definite and sharp chatoyant effect is produced.

Which Gemstones exhibit Chatoyancy?

Many species can exhibit chatoyancy including tourmaline, apatite, beryl, actinolite, demantoid garnet, scapolite, sillimanite and quartz among others but only chrysoberyl can be called simply ‘cat’s eye’, the others must be prefixed by the species name.

Tiger's eye quartz. Image by Pat Daly, Gem-A.

 Chatoyant quartz known as ‘tiger’s eye’ is the only chatoyant gem produced in abundance. It can be found in South Africa and Australia and is particularly popular for use in men’s jewellery.

Cat’s Eye Gems

Cat’s eyes commonly occur in yellow, yellow-brown and greenish-yellow. Some stones, such as cat’s eye alexandrite, can even exhibit colour change which is very rare, extremely expensive and desirable. The chatoyancy is caused by very fine needles which give a bright, sharply defined eye.

A cat's eye alexandrite appearing green in daylight and purple-red under incandescent light. Images by Charlie Bexfield, Gem-A.

 Cat’s eye can also show a mesmerising ‘milk and honey’ effect where one side of the line is milky and the other translucent. As light moves across the surface the bands part and merge like the blinking eye of a cat. This particular effect has led some to believe that the stone possesses supernatural qualities.

Read more: Exploring the Varieties of Quartz

 At 8.5 on the Moh’s scale of hardness, cat’s eye is a hard and durable stone and is especially popular in Japan for men’s jewellery due to its rarity.

 Cat’s eye was also a very popular stone for engagement rings in Victorian times, when it was known as chrysolite. Another old name allocated to this stone is cymophane which means ‘wave’ and ‘appearance’ because of its optical effects.

 Chatoyancy is an interesting and unusual effect worth looking out for to add interest to either a jewellery or mineral collection. What’s more, it doesn’t have to be expensive; actinolite, sillimanite and apatite can be found quite easily, and cat’s eye quartz is very popular and obtainable.

Do you have a passion for gemmology but don't know where to start? Why not consider trying one of our upcoming Introduction workshops?

Interested in developing your knowledge on gemmology? Take a look at our Gemmology Foundation course.

Cover image: A yellow chrysoberyl cabochon showing a cat's eye effect. Image by Pat Daly, Gem-A.

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Gem-A Photographer of the Year Competition Now Open for Entries

The Gem-A Photographer of the Year Competition returns for 2020 to discover the very best images which capture facets of the gem world in all its diversity and beauty.

Gem-A is pleased to announce that the Gem-A Photographer of the Year Competition is returning for 2020! We would like to see gripping images which represent the vast breadth and variety of the field of gemmology. If you’ve captured a truly dazzling piece of jewellery, an incredible inclusion or an eye-opening image of gem mining in the field, we want to see it!

This year's competition has three themed categories: Cover Shot, The World of Gems and Photomicrographs and Special Details.

The Categories in Detail

Cover Shot: Entries to this category should be images suitable for a magazine cover; images should be shot in portrait and feature striking subjects. Images representing the vast breadth and variety of the field of gemmology are welcomed.

The World of Gems: We want to see images that illustrate the full spectrum of gemstone culture, including people, places and finished jewellery products. Examples of subject matter may include jewellery making, gem trading, mining, finished jewellery, rough and cut gems and gem artistry. 

Photomicrographs and Special Details: This category is exclusively for photomicrographs and photographs of special gem features, for example, intriguing inclusions and visual phenomena such chatoyancy, fluoresence and colour-change - the list is extensive! 

Why Enter?

+ Win the chance to have your photograph featured in Gems&Jewellery magazine. Winners could be featured on our cover, our Last Impression or our Big Picture feature page

+ You can add the accolade of being named Gem-A’s Photographer of the Year to your portfolio

+ Entry is free and open to all

 

'Microchip' by Evgenios Petrides, a photomicrograph of an iron oxide inclusion in quartz from Brazil, was named the winner of the Gem-A Photographer of the Year Competition 2019. Image credit: Evgenios Petrides FGA.

The Prize

+ The overall winner will be gifted a £300 voucher to spend at Gem-A Instruments and one year’s free Membership of Gem-A

+ Two runners-up will win a £50 Gem-A Instruments voucher

+ All three winning entries will see their photographs published in Gems&Jewellery magazine

Danny Sanchez's 'Play of Colour in Opal from Jalisco, Mexico' made the final shortlist of Gem-A's 2019 competition. Image credit: Danny J. Sanchez.

Judging Process

+ The Gems&Jewellery editorial team will shortlist nine entries (three from each category) which will be uploaded to the Gem-A Facebook page where the public can vote for their top five.

+ A guest judge will then choose a winner and two runners-up from the final five photographs.

How to Enter

Email your entry to editor@gem-a.com. The Competition is open now and will be accepting entries until 30 September 2020. The winner will be announced on Gem-A’s Facebook page shortly after the Competition has closed.

Wim Vertriest's 'A Hard Day's Work' was a shortlisted entry in last year's competition. Image credit: Wim Vertriest FGA GG.

Competition Rules

+ A maximum of three photographs may be entered per person and each photograph must fit into at least one of the three listed categories

+ Entries must be accompanied by your name and post-nominals (if applicable)

+ Images must be captioned with a title and a description of no more than 150 words telling the story behind the photograph

+ All photographs entered into the Competition must have been taken within the last 18 months

+ The image must be your own work and not belonging to a third party

+ Photographs must be high resolution, with a minimum of 300dpi and ideally a minimum of 1mb in size

+ Please send files larger than 10mb via Dropbox.com or WeTransfer.com (these are free to use media transfer services)

+ By entering the Competition you accept that your image may be used in Gems&Jewellery magazine, on the Gem-A Blog and on Gem-A’s social media channels. You will always be credited as the creator of the work

For more information on the Competition rules, terms and conditions click here. If you have any further questions you can email editor@gem-a.com

We can't wait to see your entries - good luck!

Cover image: 'Floating Mushroom' by Billie Hughes FGA was a runner-up in last year's Gem-A Photographer of the Year Competition. The photomicrograph shows a mushroom-shaped cristobalite inclusion in amethyst. Image credit: Billie Hughes FGA.

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