An Update on Identification Features of Treated Baltic Amber

Guy Lalous ACAM EG explores a detailed characterization of Baltic amber samples treated in experiments by Wang et al.(2014) in The Journal of Gemmology, whilst discussing the criteria for identifying heat-treated amber using standard gemmological instruments, FTIR and Raman spectroscopy.

Amber is an organic gem. Organic gems are the products of living or once-living organisms and biological processes. The fossilisation process of amber involves a progressive oxidation, where the original organic compounds gains oxygen, and polymerisation, which is an addition reaction where two or more molecules join together. This process produces oxygenated hydrocarbons, which are organic compounds made of oxygen, carbon and hydrogen atoms.

What about “Beeswax amber”?

Beeswax amber is sub-translucent or opaque due to abundant microscopic bubbles.


(a) Surface features of aged beeswax amber may include oxidation cracks, as shown here on sample JD-2; note the unoxidized centrelines and only minor 'bleeding' of adjacent colour. (b) By contrast, cracks formed in beeswax amber during natural weatheing have dark centrelines with more extensive 'bleeding' of colour, as seen here on untreated amber JB-3. Photomicrographs by Y.Wang; magnified 20x.

What about “Sun spangles”?

In heat treated amber, discoidal stress fractures are produced by expansion and decrepitation after the pressure equilibrium of the bubbles within the amber has been abruptly broken. Those fractures are referred to as “Sun spangles”. The presence of large and numerous sun spangles within amber provide immediate evidence of heat treatment.

What about treatments?

The main purposes of amber heat treatment are to improve or alter the colour, enhance the clarity and produce inclusions that have an appealing visual effect (“Sun spangles”). Methods include clarifying, baking (oxidation), decrepitating and ‘beeswax ageing’.

This paper provides a detailed characterization of Baltic amber samples that have been treated in experiments by Wang et al.(2014). Standard gemmological instruments were used as well as FTIR and Raman spectroscopy to document changes in the physical, optical and spectroscopic properties of the samples before and after treatment. The formation mechanisms of the features seen in heat treated amber are discussed, and criteria for identifying heat-treated amber are presented.


'Sun spangles', or discoidal stress fractures, were exhibited by heat-treated amber samples that underwent decrepitation. They are shown here within: (a) golden fire amber JE-5 (magnified 15x) and (b) red fire amber JC-3 (20x; the red colour of this particular discoid fracture is partially obscured by yellow reflections from the surrounding amber). Photomicrographs by Y.Wang.

What about the “Baltic shoulder”?

Infra-red spectroscopy is the most effective scientific method for identifying fossil resins. With this technique broad absorptions will be witnessed in Baltic amber in the 1260-1160 cm-1 range. Those are assigned to C-O stretching vibration. These features known as “Baltic shoulder” are specific to Baltic amber and are related to the presence of succinic acid. Baltic amber, also called succinate, contains 3-8% succinic acid.

The gemmological and spectroscopic features of untreated versus treated amber are listed in the table below:

Gemmological & Spectroscopic Features Untreated Baltic Amber Treated Baltic Amber
Colour & Clarity

Yellow or light yellow beeswax

Opaque or translucent

Golden yellow, red or dark red

Transparent, some with transparent surface & opaque interior
Refractive Index 1.54

Clarified golden: 1.54 – 1.56

Oxidized red: 1.55 – 1.58
Long-wave UV Fluorescence Moderate-to-strong yellow to yellowish white

Clarified golden: weak-to-moderate dull yellow or yellowish white

Baked red: inert or weak dull yellow
Internal Features  

Sun spangles

Red flow striations
Surface Features with no re-polishing

Oxidation cracks: dark centrelines – extensive “bleeding” of colour

Oxidation cracks: narrow- minor “bleeding” of colour

Septarian cracks: irregular networks of micro-cracks showing mosaic-like appearance

Wavy surface ripples  
FTIR Spectra

Strong absorption bands at 2932 and 2867 cm-1

Absorptions at 1732 and 1702cm-1

Moderately strong absorptions at 1452 and 1378cm-1

Broad absorptions into the 1260-1160cm-1 range (“Baltic Shoulder”)

Absorptions 1645 and 888 cm-1

Decreased intensity of 2932 and 2867 cm-1 (*)

Increased intensity 1732 and 1702cm-1 (*)

Increased intensity of 1260- 1160 cm-1 (“Baltic Shoulder”) (*)

Decay to extinction of 1645 and 888 cm-1 (*)

Raman Spectra Peaks at 2932 and 2867 and 1645 and 1444 cm-1 Minor changes: The absorption intensity at 1645 cm-1 dwindles and the intensity at 1444 cm-1 increases gradually

(*) Progressively with clarification and oxidation


Untreated amber specimens from Kaliningrad Russia, were sliced into multiple pieces for heating experiements. Each sample number is shown with the total weight of all the slices. Photos by Y.Wang


Pictured here are the same samples in the pictured above following various treatment processes, as described in the text and in the table above. Photos by Y.Wang

What about the variations of the FTIR features after heat treatment?

A decrease of the absorption of the major band at 2932 cm-1 suggests that the saturated C-H bond was broken down by heating. An increase in intensity of the absorption at 1732 cm-1 suggests that oxygen involvement enables a higher concentration of the C=O functional group. The extinction of the weak absorptions at 1645 and 888 ccm-1 corresponds with the breaking of the unsaturated C=C double bond of the exocyclic methylene group. Heat treatment leads to fewer saturated C-H bonds and unsaturated C=C double bonds in amber, in correlation with more oxygen-bearing functional groups and higher degree of polymerization.

What about the variations of the Raman features after heat treatment?

FT-Raman spectra indicate that the number of saturated C-H bonds (1444 cm-1) consumed by oxidation during amber heat treatment is greater than that of unsaturated C=C double bonds (1645 cm-1) consumed during the process, and thus higher intensity ratio (I : 1645 cm-1/I = 1444 cm-1) indicate a greater degree of oxidation.


Representative FT-Raman spectra are shown for sample groups JA and JD, both before and after heat treatment.

What are the conclusions reached for the spectral intensity ratios after heat treatment?

FTIR: An intensity ratio of ≤ 1.54 for the 2932 and 1732 cm-1 bands is indicative of clarified amber, while ≤ 0.50 correlates to baked amber, the range of ~ 1.5 – 1.9 is not considered diagnostic. Raman: The minor changes in intensity ratios are not considered as being diagnostic for identifying heat treatment.

The treatments of amber are increasing in number and complexity. Baltic amber is the most versatile when it comes to treatments.

This is a summary of an article that originally appeared in The Journal of Gemmology entitled ‘Gemmological and Spectroscopic Features of Untreated vs. Heated Amber’ by Yamei Wang, Mingxing Yang, Shufang Nie and Fen Liu 2017/Volume 35/ No. 6 pp. 530-542

Interested in finding out more about gemmology? Sign-up to one of Gem-A's courses or workshops.

If you would like to subscribe to Gems&Jewellery and The Journal of Gemmology please visit Membership.

Cover image: Golden amber pendant (upper left, 36.65 g), a bicoloured fire amber pendant (upper right, 22.59 g), a red amber necklace (96.27 g) and an aged beeswax bracelet (45.31 g). Photo by Y.Wang.


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: Garnet For Those Born In January

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If you're lucky enough to be born in January, vibrant garnet is your birthstone. A rainbow jewel of the gem world, garnet displays the greatest variety of colour of any mineral and is very often untreated, making it a rarity in the gem world. 

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Getting Started with Quartz Inclusions

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Do you know your calcite inclusions from your dumortierite, epidote, fluorite and rutile? Here, Charles Bexfield FGA DGA EG explores some incredible quartz inclusions and explains what to look for when shopping for quartz specimens.

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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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Understanding the Cat's Eye Effect in Gemstones

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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 Lifecycle Of A Sapphire Rush

In the last 12 months, an exceptional sapphire rush in eastern Madagascar saw thousands of people searching for precious treasure in one of the poorest places on earth. Rosey Perkins GG, an independent gemmologist based in London, shares this report from two visits to the island nation.

A sapphire rush that started in September 2016 has produced world class sapphires close to the village of Bemainty, in the wet forest of eastern Madagascar has reached upwards of 45,000 people. The mine site was in an area called Corridor Ankeliheny-Zahamena (CAZ), which is designated for conservation and managed by Conservation International on behalf of the Government of Madagascar.

I gained access to the mines near the village of Bermainty in October 2016 and May 2017 and was able to capture the lifecycle of the mines that has become known as 'Tananarive Carrier' (18°00'00"N 48°67'83").

'Tananarive', which is the capital city of Madagascar, refers to its size and 'carriere' is Malagasy for 'mine'. It lies 135km NE of the capital and is accessed via the nearest town of Ambatondrazaka. From here a motorbike can be taken to the trailhead at Ansevabe. On 21 October 2016, the President of Madagascar had declared the mining activity illegal because it was inside CAZ. I arrived at the mine the following day. There was a sense of urgency and camaraderie as the miners anticipated imminent government intervention.


1: 100ct sapphire from Bemainty Mines.

The gendarme were present at the site to keep peace and monitor the mining activity. The mine was highly productive and in Ambatondrazaka, I was shown high-quality blue sapphire up to 50g, as well as desirably-coloured pink-orange sapphires, reportedly mined at Bermainty (1). However, in February, the Swiss Gemmological Institute (SSEF) issues a trade alert with the warning that sapphires from these mines were being misreported as Kashmiri (Krzemnicki, 2017). A preliminary study of sapphires from this deposit indicated that the origin of these sapphires would prove challenging for laboratories and that more in-depth analysis was needed (Pardieu, 2017). For this reason, Lotus Gemology needed samples and so it was thanks to them and Association Française Gemmologie that I returned on May 6, 2017.

At 5am, I started climbing the path towards the mine and 10 hours later, we reached the valley that had heaved tens of thousands of people in October. It was a wide valley carved with pits but in May 2017 only about 500 miners remained. The southern end had been almost abandoned and work was concentrated in the more productive central and northern areas, where old pits two to three metres deep were being reworked. Miners had left due to illness, lack of funding or to return to their previous jobs. In the nearby valleys that had been explored, many groups hadn't found a stone for months. (2&3).


2. Tananrive Carrier facing North in October 2016.


3: Tananrive Carrier in May 2017. Image by Rosey Perkins.

However, the mining area had been a valuable source of income during the months that the local population had waited for the rains, which came later than usual. They arrived as miners, porters or cooks to feed the growing community. Soon the exploration had moved into the adjoining valleys, which were named Milliard 1-4. In May, shreds of blue tarpaulin attached to the top of poles marked abandoned claims and only the skeletons of abandoned huts remained. Morale was low in the valleys, but a few months earlier they had been a source of hope (4).

At Tananarive Carrier families lived in two story huts and many had tents on the first floor with shops beneath. These were stocked with beer, local rum, vegetables and plenty of meat. There was a hut for gambling, a cinema with a projector and a board of power sockets offering electricity to charge mobile phones. There were two churches and a mosque but still no school and no sanitation. A doctor had visited for the month of November but the gendarme (law enforcement) said another was needed.


4: Abandoned section of Milliard 3. 'Milliard is French for 'Billion' and a billion ariary (the currency of Madagascar) worth of stones - approximately £300,000 - had been found in each.

Trading was open and the gendarme was relaxed. At the start of the rush there were many independent 'cooperatives' but in May 2017 most were from other mining areas in Madagascar, such as Diego Suarez, Sakahara and Fort Dauphin. Mining activity was mainly sponsored by businessmen from the major cities. They financed another 'sponsor' who stayed at the mine and hired men in groups, providing food and equipment in exchange for first refusal on the stones they found. At Tananarive Carrier I met an independent sponsor who employed 16 miners, eight security guards and a woman who cooked their meals. His miners formed two groups and shared the use of a motor pump. He supplied the equipment for digging, the fuel for their motor and food for the men. He said he spent approximately $35 per week on rice and meat for the miners and expected to sell a sapphire with 30%-40% profit.

Ambodipaiso and Sahambato were two mining communities that had sprung up by miners leaving Tananarive Carrier (5). They had stopped at a river, camped and dug a test pit or panned for gold and found sapphires. Movement between them was fluid and, as a large sapphire was found at one site, the response was an influx of people (6).


5: Ambodipaiso on May 6th 2017. Image courtesy of Zanaky Ny Lalana.

As miners continue to explore this gem-rich earth of eastern Madagascar, there may be a great many more rushes in the area (Pardieu 2017). While the Government of Madagascar has declared the mining activity illegal, they have not brought it to a halt. The media's coverage of this story has not portrayed the gem industry favourably and, as mining continues, pressure will be on the gem and jewellery industry to respond.

Impact assessments are being carried out by independent consultancies on behalf of businesses sourcing gemstones in Madagascar and the response is likely to be rehabilitation programmes in areas of land damaged by mining activity. A collective effort to support conservation would help sustain Madagascar's biodiversity and also demonstrate the gem industry's commitment to responsible sourcing.


6: Sapphires from Sahambato which resulted in an influx of people to the area.

Acknowledgements: Permission to enter CAZ was given by the Prefecture D'Ambatondrazaka, Direction Regionale de L'Environment De L'Ecologie et de Forets and the Bureau du Cadastre Minier de Madagascar. The gendarme permitted our team four days inside the areas and gave us two policemen as security guards. Thank you to Institute Gemmologie de Madagascar, Association Francaise de Gemmologie, Lotus Gemology and Vincent Pardieu for their time and support.

Gem-A members can log in to read the full article Gems&Jewellery Autumn 2017 / Volume 26 / No. 3

Interested in finding out more about gemmology? Sign-up to one of Gem-A's courses or workshops.

If you would like to subscribe to Gems&Jewellery and The Journal of Gemmology please visit Membership.

Cover image: The team walking from Ansevabe towards the miners. Two gendarmes (local police) joined them as a security measure. In October 2016, Rosey had counted 1,000 people travelling towards the mine. In May 2017 we passed less than 50. All images by Rosey Perkins, unless otherwise stated.


The Fascinating History of Antique Turquoise Jewellery

The Fascinating History of Antique Turquoise Jewellery

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Birthstone Guide: Garnet For Those Born In January

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Birthstone Guide: Turquoise For Those Born In December

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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Jade has long been revered by gem lovers internationally, but nowhere more so than in China. But what is it that makes this gemstone so special? Gem-A's Assistant Gemmology Tutor Dr Juliette Hibou FGA gives us an overview of jade, how to identify it and its significance in Chinese culture.

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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 Ethics of Coral Jewellery and Sourcing for Gemmologists

December 2017: An Update from the Author 

No matter how much any information has been checked prior to publication, it is always possible that – sooner or later - some facts are proved incorrect. An author may be contacted by a person who has read an article and has more information on the subject, and of course with time new research often uncovers new details that were simply not available when a book or an article was written. 

Whitby jet comes into the latter category as it has been the subject of research in recent years. We have long believed it to derive from the wood of one species of tree only (a species of Araucaria), but now research proves that it in fact derives from half a dozen or so tree or plant species. As yet nothing has been published about it, but we look forward with great anticipation to a paper on the subject. It is exciting news, and means that most of the accepted gemmological texts will need to be re-written. The updated knowledge does not, however, diminish the quality of good Whitby jet which is still of the highest order: very uniform, homogenous, deep black, and it takes a very high polish.

Since writing about corals in the Autumn issue of G&J, more information has come my way from Italy about the condition of the coral beds in the Mediterranean. I am assured that they are healthy, and that the fishing is now so tightly controlled by licencing and fishing methods (scuba diving only, size of coral permitted to be harvested, quota and permitted areas), that Corallium rubrum can be traded without a danger of over-fishing. These corals grow in deep waters, so are also less affected by changes in the sea temperatures and pollution. It is good to know that the situation is controlled and that we may continue to enjoy precious coral, but, as with all gem materials, I would always advocate buying only from a reputable source.

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A Connection to Coral: Gems&Jewellery Autumn 2017 Vol 26 No.3

Coral may not inspire the same emotional outpouring as ivory, but its delicate ecosystem needs to be protected, says Gem-A president Maggie Campbell Pedersen FGA ABIPP.

Coral has a long and rich history. Red coral has been found in Neolithic graves and two thousand years ago was much sought-after by the Chinese. The Ancient Greeks preferred black coral, while in some African countries red coral beads signified wealth. Few gem materials have been believed to have such powers as coral, both talismanic and medicinal. For example, it was thought that coral could cure madness, could strengthen babies' teeth, and that it turned pale when worn by someone who was sick. A piece of coral above the door of a house would protect its inhabitants, or its wearer from being struck by lightning.

Coral use today is more limited and consists of some jewellery and carvings. It does not have the same emotive impact as some other organic gem materials (notably ivory), yet it is understood that corals are vital to marine eco-systems and that they are threatened, and it should perhaps be remembered that they are animals, not plants - albeit tiny headless ones (called polyps).

The coral used in past times in Europe was predominantly the red Corallium rubrum (often termed 'precious coral' by the gem trade), mainly from the Mediterranean. In recent years we have used several different species of coral, originating from many different seas and oceans.

World-wide, coral beds are diminishing. Each species of coral needs different conditions to flourish, but all of them are extremely sensitive to alterations in the temperature of the water and in the acidity of the sea. Our coral fishing methods have been refined and we are far more aware of the risks of over-fishing, but the threats to corals of global warming and pollution remain, and many believe that corals are still being over-fished.


1: Different colours of Corallium corals.

Most corals consist of a white core - the 'communal skeleton' - made of calcium carbonate in the form of aragonite or calcite. They are covered by 'flesh' which consists mainly of tiny polps connected to each other by living tissue. In most corals the tissue also contains algae called zoolxanthellae with which the corals live in a symbiotic relationship. It is the algae that give the living corals their wonderful colours. In only a few of them is the calcium carbonate 'skeleton' coloured (1).

Global warming is causing ocean temperatures to rise, which can result in 'coral bleaching' - a phenomenon where large areas of corals reject their vital algae (zooxanthellae) and consequently die off, losing their coloured fleshy covering and leaving just the white skeletons. Corals grow very slowly - some at a rate of a few millimetres per annum - so it takes from 10 to 20 years for a reef to regenerate. As coral bleaching is today happening more often it is becoming less likely that the corals can recover, hence the worry about the Great Barrier Reef off Australia's north-east coast, and also the reefs around Belize.

The phenomenon affects reef corals because they grow in shallow water, however, of our gem corals only blue coral is a reef coral, and all other gem corals are either solitary or colonial in habit. They live on the seabed and grow at greater depths where they are less vulnerable to changes in the water temperature. Despite this, they are still sensitive to the raised acidity of the water and rising sea levels caused by global warming, and to all pollutants that find their way into the oceans. A further risk to their survival is physical impact which breaks them, for example caused by fishing nets, or divers. But perhaps their greatest threat has been over-fishing for the gem trade.

Corallium corals grow in colonies, and have a tree-like appearance (2). They range from white through shades of pink, salmon, and blood red to deep red. There are several Corallium varieties, of which C.rubrum is the best known. The Latin names of a number of the others are at present being changed - a frequent occurrence with corals. The colour in Corallium corals is in the hard skeleton, as they lack zooxanthellae.


2: Unpolished branch of Corallium rubrum showing the tree-like shape.

The coral is recognised by the tiny striations along its 'branches', which are still visible after cutting and polishing as they penetrate the entire skeleton. They are about 0.25-0.5 mm apart. The material takes a very high, porcelaineous polish (3).

Corallium coral is found in the Mediterranean and around Japan, China, and other areas of the Pacific. Fishing is now being regulated in several of these areas due to extremely depleted coral beds, and the rarity of the material is reflected in its price. It has been suggested that some Coralliums should be included in the CITES Appendices (the Convention on International Trade in Endangered Species of Wild Fauna and Flora), but this has not happened as the trade prefers to regulate itself. Methods being used include rotating areas where fishing is permitted, specifying the amount and minimum size of coral taken, the number of licenses granted, and the equipment used.


3: Detail of Corallium rubrum beads, showing structure and high lustre.

Torre de Greco (on the outskirts of Naples in Italy), has been a famous centre for coral carving for hundreds of years. Today the large companies cannot rely entirely on local coral to meet demand, so make up the shortfall - about 30%- from the Far East. The Mediterranean raw material is generally smaller in size, so larger items are carved from the Far Eastern material.

Several years ago at gem fairs such as those in Tuscon, bamboo coral (of the family Isididae), was sold in abundance, but today we see only small amounts for sale. A beige colour in its natural state, it is bleached and dyed, usually red or orange. It is a heavy material, and although the outer surface displays longitudinal striations similar to Corallium corals also have a growth habit resembling that of a tree, but they have nodes of organic material called gorgonian between the internodes of calcium carbonate. These characteristics limit the coral's use, and it is most commonly seen sliced into discs and used as beads, or as simple carvings. Occasionally it is seen imitating Corallium coral. It has been so popular that the coral beds are now severely depleted (5).


4: Bamboo coral: natural coloured rough, dyed rough, and dyed beads.

Heliopora coerulia or blue coral is found in many parts of the Indo-Pacific region and in the Great Barrier Reef. It appears on CITES Appendix II, indicating that it is permissible to trade but only under very strict conditions, and licences are required. It is a reef coral with a blue aragonite skeleton - one of only two reef corals with a coloured skeleton - and is massive in form rather than tree-like. It is covered in tiny holes in which the polyps lived (6).


6: Blue coral, Heliopora coerulia: rough and polished beads.

Some years back another red coral began to appear on the gem market: Melithaea ocracea. It is often called red sponge coral. It belongs to the family of soft corals, which create a less compact skeleton. Though it is still rigid, it is less stable as a gem material and is usually impregnated with a resin to stabilise it and to enable it to be polished to a satin finish. The resin also makes it much more comfortable to wear as it is a very rough material in its untreated state. It is naturally a red colour in the beige veins. It is found in the Indian and Pacific Oceans, and the China Seas (7).


7: Melithaea ocracea: polymer impregnated disc, colour enhanced beads (inner row) and reconstructed (chips in a red polymer, outer row).

Black and golden Antipatharia corals are found around the Philippines and Indonesia. They are also listed on CITES Appendix II. They differ from other corals in that their skeletons are made up of organic matter (closely related to keratin), not of calcium carbonate. Although flexible when growing, the material becomes rigid after fishing (8).

Golden corals are rare, but black Antipatharia can be bleached to a golden colour, and is often sold as a natural material. Once popular at gem fairs in the form of loose beads, black or bleached material is still occasionally encountered today, and is generally sold as 'old stock'.

There are other coral not mentioned here that can be used for jewellery or objets d'art, and not all are listed by CITES - often because they have not been adequately researched. It is incumbent upon the buyer or seller to check a species' status, which can be problematic as coral is notoriously difficult to identify when it has been cut and polished.

In the EU, licences must be obtained (e.g. from APHA, the Animal and Plant Health Agency in UK), for any corals that are listed by CITES on Appendix II. Each request is considered individually with many criteria taken into account. Other countries have different guidelines, sometimes stricter than ours, for example the beautiful Kulamanamana haumeaae golden coral from Hawaii is not listed by CITES, but is protected by US law.


8: Black Antipatharian coral, genus Leopathes: rough, and polished beads.

Some coral jewellery is still sold at the high-end of the market, beautiful items are still being produced in coral in the Far East, and there is still a coral industry around the Mediterranean, but generally not nearly as much coral is being worked today as in times past, partly due to fashion, partly due to the rarity of raw material, and partly because there are many people who feel that corals are too endangered and vulnerable should not be fished.

Attempts have been made at culturing corals, but so far it is a tiny industry, targeted mainly at the aquarist market where small corals are a popular addition to tropical fish tanks. Gem corals grow too slowly to make it a feasible alternative to wild-caught corals.

We do not emotionally equate the use of coral with that of ivory, but corals play a significant role in marine ecosystems and need to be protected, and failure to do so will eventually result in a total ban. Meanwhile the gem trade should ensure that any coral purchased is reliably sourced.

Gem-A members can log in to read the full article Gems&Jewellery Autumn 2017 / Volume 26 / No. 3

Interested in finding out more about gemmology? Sign-up to one of Gem-A's courses or workshops.

If you would like to subscribe to Gems&Jewellery and The Journal of Gemmology please visit Membership.

Cover image: Corals for sale at the Tuscon fairs in 2008. All images ©Maggie Campbell Pedersen.


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.

Read more


Birthstone Guide: Garnet For Those Born In January

Birthstone Guide: Garnet For Those Born In January

If you're lucky enough to be born in January, vibrant garnet is your birthstone. A rainbow jewel of the gem world, garnet displays the greatest variety of colour of any mineral and is very often untreated, making it a rarity in the gem world. 

Read more


Getting Started with Quartz Inclusions

Getting Started with Quartz Inclusions

Do you know your calcite inclusions from your dumortierite, epidote, fluorite and rutile? Here, Charles Bexfield FGA DGA EG explores some incredible quartz inclusions and explains what to look for when shopping for quartz specimens.

Read more


Understanding Iridescence: Opals, Pearls, Moonstones and Fractured Stones

Understanding Iridescence: Opals, Pearls, Moonstones and Fractured Stones

Iridescence has to be one of the most mesmerising and magical optical effects seen in gemstones. But have you ever wondered how it occurs? Gem-A's Collection Curator Barbara Kolator FGA DGA shines a light on this fascinating optical effect and tells us about the gems that are most likely to display it.

Read more


Hidden Treasures: Highlights of Gem-A's Gemstones and Minerals Collection

Hidden Treasures: Highlights of Gem-A's Gemstones and Minerals Collection

Gem-A Gemmology Tutor Pat Daly FGA DGA offers us a glimpse at some of the more unusual items in Gem-A's Gemstones and Minerals Collection.

Read more


Tanzanite: The Contemporary December Birthstone

Tanzanite: The Contemporary December Birthstone

Are you looking for the perfect festive gift for a December baby? Gem-A tutor Lily Faber FGA DGA EG considers tanzanite – one of three birthstones for December – and shares how this relatively new gemstone compares to its purple and blue-hued rivals.

Read more


Birthstone Guide: Turquoise For Those Born In December

Birthstone Guide: Turquoise For Those Born In December

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...

Read more


Understanding the Cat's Eye Effect in Gemstones

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 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.

Read more


Jade and its Importance in China

Jade and its Importance in China

Jade has long been revered by gem lovers internationally, but nowhere more so than in China. But what is it that makes this gemstone so special? Gem-A's Assistant Gemmology Tutor Dr Juliette Hibou FGA gives us an overview of jade, how to identify it and its significance in Chinese culture.

Read more


Highlights of Gem-A Conference 2019

Highlights of Gem-A Conference 2019

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!

Read more


 

Additional Info

Read more...

110 Years of Gemmology

It all started with an idea...

Manchester, England, 1908
110 years ago today, on July 6 1908, Samuel Barnett a jeweller from Peterborough, stood up at a gathering of the National Association of Goldsmiths to propose an idea: to offer lessons and examinations in gemmology to support the jewellers’ industry. 

The UK’s leading goldsmiths and jewellers supported the idea and created an official committee to advocate gemmological education. In that moment, Barnett established the UK as the world’s first provider of gemmological education, and became the father of what would one day become Gem-A. As another Gem-A founding father, Basil Anderson, noted many years later, Barnett’s proposal "marked the beginning of organised gemmology, not only in this country, but in the whole world".

 
G.F Herbert Smith

This was an exciting time of innovation in the gemmological world. The years building up to Barnett’s proposal had already seen the arrival of the Steward Refractometer in 1905, followed by the Goniometer and Spectroscope in 1907. Renowned mineralogist Dr G.F Herbert Smith was also developing his ground-breaking book Gemstones, released in 1912, offering the first textbook on gemstones with full instructions on how to use specialist equipment. While the gems and jewellery industry was an ancient trade, this equipment enabled jewellers to now look inside their stones, and these years mark the first advances in practical gemmology.

London, 1913
Within five years of Samuel Barnett’s proposal the first gemmological examinations were held, set and marked by Herbert Smith, with Barnett himself receiving the first ever Diploma in Gemmology. 

Since 1913, gemmology has gone from strength to strength, with the continued ethos of serving the industry through championing access to gemmological education.

In 1938 we officially became the Gemmological Association of Great Britain, and over the last century we have seen a prestigious line of Gem-A presidents, including internationally renowned gemmologists, inventors and even Nobel Prize winners. Over the next coming months our 'Heritage Series' will showcase these Gem-A Greats and their contributions to the advancement of gemmology and the wider scientific community.

From an idea in 1908, today Gem-A’s Gemmology and Diamond Diplomas are taught in 40 Accredited Teaching Centres across the world and our FGA and DGA members are internationally recognised by the industry.

Between now and the Gem-A Conference in November we will be celebrating the last 110 years of gemmology and our proud history of being the world’s first provider of gemmological education. So keep an eye out for the latest 'Heritage Series', where we will explore our illustrious founders, including Herbert Smith, Basil Anderson, and Sir Lawrence Bragg.


Gem-A Graduates 2017

 

If you would like to join us in celebrating 110 years of gemmology education click here and register for the Gem-A Conference 2018.

If you are a Gem-A Member or Student you will receive an email with an access link, if you haven't received it please contact membership@gem-a.com.

 


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.

Read more


Birthstone Guide: Garnet For Those Born In January

Birthstone Guide: Garnet For Those Born In January

If you're lucky enough to be born in January, vibrant garnet is your birthstone. A rainbow jewel of the gem world, garnet displays the greatest variety of colour of any mineral and is very often untreated, making it a rarity in the gem world. 

Read more


Getting Started with Quartz Inclusions

Getting Started with Quartz Inclusions

Do you know your calcite inclusions from your dumortierite, epidote, fluorite and rutile? Here, Charles Bexfield FGA DGA EG explores some incredible quartz inclusions and explains what to look for when shopping for quartz specimens.

Read more


Understanding Iridescence: Opals, Pearls, Moonstones and Fractured Stones

Understanding Iridescence: Opals, Pearls, Moonstones and Fractured Stones

Iridescence has to be one of the most mesmerising and magical optical effects seen in gemstones. But have you ever wondered how it occurs? Gem-A's Collection Curator Barbara Kolator FGA DGA shines a light on this fascinating optical effect and tells us about the gems that are most likely to display it.

Read more


Hidden Treasures: Highlights of Gem-A's Gemstones and Minerals Collection

Hidden Treasures: Highlights of Gem-A's Gemstones and Minerals Collection

Gem-A Gemmology Tutor Pat Daly FGA DGA offers us a glimpse at some of the more unusual items in Gem-A's Gemstones and Minerals Collection.

Read more


Tanzanite: The Contemporary December Birthstone

Tanzanite: The Contemporary December Birthstone

Are you looking for the perfect festive gift for a December baby? Gem-A tutor Lily Faber FGA DGA EG considers tanzanite – one of three birthstones for December – and shares how this relatively new gemstone compares to its purple and blue-hued rivals.

Read more


Birthstone Guide: Turquoise For Those Born In December

Birthstone Guide: Turquoise For Those Born In December

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...

Read more


Understanding the Cat's Eye Effect in Gemstones

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 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.

Read more


Jade and its Importance in China

Jade and its Importance in China

Jade has long been revered by gem lovers internationally, but nowhere more so than in China. But what is it that makes this gemstone so special? Gem-A's Assistant Gemmology Tutor Dr Juliette Hibou FGA gives us an overview of jade, how to identify it and its significance in Chinese culture.

Read more


Highlights of Gem-A Conference 2019

Highlights of Gem-A Conference 2019

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!

Read more


 

Additional Info

Read more...

Sir Henry A. Miers - Gem-A's First President

'Curiouser and Curiouser', said the Gemmologist

On July 6, Gem-A celebrated the anniversary of 'organised gemmology education', the idea proposed by Peterborough jeweller and one of Gem-A's founding fathers, Samuel Barnett. For the second instalment of our Heritage Series we turn to Gem-A's very first president, Sir Henry A. Miers F.R.S, the eminent mineralogist and crystallographer who became Gem-A president in 1932.

In his lectures for the Royal Society in 1896 on ‘Precious Stones’, Henry Miers aimed to highlight the importance of considering, not just the history or artistic interest of gemstones, but some of their more curious properties.

By examining their refractive index and specific gravity, Miers demonstrated how instruments such as the goniometer, refractometer, dichroscope, and polariscope helped to determine the identity of gemstones beyond opinion to scientific proof: ‘the methods are those of physical science – and they are accurate’ (Miers 1896, Scientific American, 17309)


From the 'Precious Stones' article  (Miers 1896, Scientific American, 17309)

Observing the number of serious mistakes made in the jewellery trade in the 1890s, Miers despaired that ‘the jeweller’s trade stands almost alone…in ignoring the aid of physical science’ and in these lectures, published in Scientific American, he championed the ‘absolute necessity of accurate scientific knowledge’ to identify gemstones (and their imitations).

Graph detailing SG and RI from the 'Precious Stones' article  (Miers 1896, Scientific American, 17309)

In just over a decade’s time in Manchester July 1908, Samuel Barnett would propose the establishment of organised gemmological education to the National Association of Goldsmiths, and Miers’ call for applied gemmology in the jewellery industry would become a reality.

Read more: 110 years of Gemmology

For Miers, those fortunate enough to delve into the world of gemmological science were intrepid explorers, and in their ‘attempt to explain all these curious properties, will find themselves in a most fascinating field of discovery and speculation.’ (Miers 1896, Scientific American, 17309)

It was a world that Miers remained in for his entire life.
A King’s Scholar of Eton College, the young Henry went to Trinity College, Oxford, on a classics scholarship, before transferring to mathematics. From Oxford, Miers joined the Mineral Department of the British Museum (Natural History) under Lazarus Fletcher in 1882 and – like many of his Gem-A successors – went on to become Keeper of the Minerals.

At the British Museum, Miers arranged the mineral gallery and the crystallography catalogue, while also lecturing in crystallography at Central College, South Kensington, and publishing his research on precious stones and the morphology of various minerals.


Gem-A's collection of Miers' work

Remaining in the fascinating field of discovery that is gemmology, Miers was offered the Chair of Mineralogy in 1895 at Magdalen College, and on his return to Oxford he improved their laboratory and the University’s mineral exhibition. Miers was also made a fellow of the Royal Society in 1896 and in 1902 published his seminal work Mineralogy: an introduction to the scientific study of minerals, before becoming president of the Mineralogical Society for 1904/5.

Read More: Gem-A History 1908-Present

In 1912 he was knighted, and in 1915 became the Vice-Chancellor and Professor of Crystallography at Manchester, which under Ernest Rutherford became a hub for nuclear physics and crystallography, attracting the likes of the Nobel Prize Winner Sir Lawrence Bragg - who likewise would go on to become Gem-A president!

Sir Henry Alexander Miers, Gem-A's President 1932-37.
National Portrait Gallery, London, Creative Commons.

In 1926, Miers returned to London and became a trustee of the British Museum. He was appointed to the Royal Commission for National Museums and Galleries, a role that took him around the UK and the world: the Carnegie UK trust invited him to report on museums across Britain, and then for the Carnegie Corporation in New York. He went on to Canada and British Africa in 1932. It was at this time that Sir Henry was approached to become the first president of the (then) Gemmological Association, a post he held until 1937.

Printed Works of Gem-A Greats featured in our 2018 Heritage Series. 

Sir Henry Miers died peacefully at home on 10 December 1942, aged 85, as arguably one of the first trailblazers of gemmology. He was held in such high esteem that it was the equally renowned Dr Herbert-Smith who wrote his obituary in Nature. It is to Herbert-Smith we will turn to in our next instalment of Gem-A’s ‘Heritage Series’.

If you would like to join us in celebrating 110 years of gemmology education click here and register for the Gem-A Conference 2018.

If you are a Gem-A Member or Student you will have received an email to book member or student rates, if you haven't received it please contact membership@gem-a.com.

Cover Image: Sir Henry Alexander Miers by Lafayette, whole-plate film negative, 30 May 1929, NPG x69585 © National Portrait Gallery, London, Creative Commons. 


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.

Read more


Birthstone Guide: Garnet For Those Born In January

Birthstone Guide: Garnet For Those Born In January

If you're lucky enough to be born in January, vibrant garnet is your birthstone. A rainbow jewel of the gem world, garnet displays the greatest variety of colour of any mineral and is very often untreated, making it a rarity in the gem world. 

Read more


Getting Started with Quartz Inclusions

Getting Started with Quartz Inclusions

Do you know your calcite inclusions from your dumortierite, epidote, fluorite and rutile? Here, Charles Bexfield FGA DGA EG explores some incredible quartz inclusions and explains what to look for when shopping for quartz specimens.

Read more


Understanding Iridescence: Opals, Pearls, Moonstones and Fractured Stones

Understanding Iridescence: Opals, Pearls, Moonstones and Fractured Stones

Iridescence has to be one of the most mesmerising and magical optical effects seen in gemstones. But have you ever wondered how it occurs? Gem-A's Collection Curator Barbara Kolator FGA DGA shines a light on this fascinating optical effect and tells us about the gems that are most likely to display it.

Read more


Hidden Treasures: Highlights of Gem-A's Gemstones and Minerals Collection

Hidden Treasures: Highlights of Gem-A's Gemstones and Minerals Collection

Gem-A Gemmology Tutor Pat Daly FGA DGA offers us a glimpse at some of the more unusual items in Gem-A's Gemstones and Minerals Collection.

Read more


Tanzanite: The Contemporary December Birthstone

Tanzanite: The Contemporary December Birthstone

Are you looking for the perfect festive gift for a December baby? Gem-A tutor Lily Faber FGA DGA EG considers tanzanite – one of three birthstones for December – and shares how this relatively new gemstone compares to its purple and blue-hued rivals.

Read more


Birthstone Guide: Turquoise For Those Born In December

Birthstone Guide: Turquoise For Those Born In December

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...

Read more


Understanding the Cat's Eye Effect in Gemstones

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 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.

Read more


Jade and its Importance in China

Jade and its Importance in China

Jade has long been revered by gem lovers internationally, but nowhere more so than in China. But what is it that makes this gemstone so special? Gem-A's Assistant Gemmology Tutor Dr Juliette Hibou FGA gives us an overview of jade, how to identify it and its significance in Chinese culture.

Read more


Highlights of Gem-A Conference 2019

Highlights of Gem-A Conference 2019

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!

Read more


 

Additional Info

Read more...

Dr Herbert Smith: Innovator, Inventor, Gem-A President

Dr Herbert Smith was Gem-A President from 1942 until 1953. He was integral in the development of gemmology for the jewellery trade and had an extensive list of accomplishments throughout his career and tenure as president: 
- He developed the Herbert Smith refractometer which, as Noel Heaton noted, improved the instrument beyond recognition and provided the industry with a means to determine the refractive index of a gemstone in a matter of seconds (without even needing to remove it from a setting).

From Nature 25 May 1911 

- He not only discovered a new mineral (paratacamite), but also has one named after him (Herbertsmithite).

- His seminal work Gem-Stones 1912 is well known to students and jewellers alike, as the first text book on gemmology with full instructions on how to use specialist equipment.

- Maybe you are are Gem-A student or graduate who has studied in the Herbert Smith room here at Gem-A HQ in London.

- You may have even bought a postcard featuring collections from the British Museum – this idea was born from Herbert Smith and is a tradition that continues today.

READ MORE: 110 Years of Gemmology

Mineralogy at the British Museum (Natural History)
Like Henry Miers before him, the young Herbert Smith went to Oxford – specialising in mathematics and physics, and then likewise went on to join Sir Lazarus Fletcher’s Department of Mineralogy at the British Museum (Natural History) in 1897 where he soon specialised in crystallography and in the use of instruments to identify faceted gemstones.

Through this work he invented the three-circle goniometer and designed an updated refractometer which, in doing so, ‘put in the hands of jewellers an instrument that all could use effectively with very little difficulty’ (W. Campbell-Smith). 

Demonstration of the Herbert Smith Refractometer in the 1912 'Gem-Stones'

In 1912 Herbert Smith published the pioneering work Gem-Stones, which was the first systematic approach to gemmology, and importantly, accessible gemmology. As he noted in his preface:

‘If this book be found by those engaged in the jewellery trade
helpful in their everyday work, and if it wakens in readers generally
an appreciation of the variety of gems, and an interest in the wonderful
qualities of crystallised substances, I shall be more than satisfied’

(Gem-Stones 1912: viii)

READ MORE: Gem-A's first President: Sir Henry Miers

Legacy at Gem-A
Maintaining this purpose, when the National Association of Goldsmiths enacted Barnett’s 1908 proposal for gemmological examinations, it was Herbert Smith who set and marked the first Gemmology Diploma, he remained at the core of the educational committee that became the Gemmological Association in 1931. 

The Gemmology Diploma examination from 1933, marked by Herbert Smith

To this day Gem-Stones is a gemmological treasure and its multiple editions have involved contributions from some of the other stalwarts throughout Gem-A history including: R.Webster, B.W Anderson, G.F Andrews and G.F. Clarringbull.

Various editions of Herbert Smith's 'Gem-Stones' from the Gem-A Collection

Herbert Smith went on to become Gem-A president in 1942, succeeding the Nobel Prize Winning crystallographer Sir William Bragg, and remained so until his death in 1953.

READ MORE: Journal Digest: Delve into the Colours of Rainbow Lattice Sunstone

During this time he was also – like many of Gem-A's previous Presidents – Keeper of the Minerals at the British Museum (NH), and he spent much of his professional life in service to the Museum. He championed inclusivity and outreach through his work with Gem-A, the Civil Service Arts Council, the Society for the Promotion of Natural Reserves, and the Wild Plant Conservation Board. He was also a part of the British delegation to the International Conference for the Protection of Nature at Bruunen in 1947.

Handwritten dedication by Herbert Smith in his 'Gem-Stones' to his daughter Jeanne
May 1912

He was a fellow of the Royal Astronomical Society, a member and vice-president of the Mineralogical Society, a fellow of the Geological Society and a member of the British Association. To top it all off, in 1949 he was awarded a CBE.

It is fair to say that without Herbert Smith, Gem-A and gemmology as we know it today would not have been possible. He was a pioneer of gemmology for the jewellery industry, a Gem-A examiner from 1913 to 1951 and he cultivated knowledge throughout his life and shared it with others.

READ MORE: Gem Empathy Competition Returns for IJL 2018

If you would like to join us in celebrating 110 years of gemmology education click here and register for the Gem-A Conference 2018.

If you are a Gem-A Member or Student you will have received an email to book member or student rates, if you haven't received it please contact membership@gem-a.com.

Cover Image: Portrait of Herbert Smith, which hangs in the Herbert Smith Room at Gem-A HQ in London.


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.

Read more


Birthstone Guide: Garnet For Those Born In January

Birthstone Guide: Garnet For Those Born In January

If you're lucky enough to be born in January, vibrant garnet is your birthstone. A rainbow jewel of the gem world, garnet displays the greatest variety of colour of any mineral and is very often untreated, making it a rarity in the gem world. 

Read more


Getting Started with Quartz Inclusions

Getting Started with Quartz Inclusions

Do you know your calcite inclusions from your dumortierite, epidote, fluorite and rutile? Here, Charles Bexfield FGA DGA EG explores some incredible quartz inclusions and explains what to look for when shopping for quartz specimens.

Read more


Understanding Iridescence: Opals, Pearls, Moonstones and Fractured Stones

Understanding Iridescence: Opals, Pearls, Moonstones and Fractured Stones

Iridescence has to be one of the most mesmerising and magical optical effects seen in gemstones. But have you ever wondered how it occurs? Gem-A's Collection Curator Barbara Kolator FGA DGA shines a light on this fascinating optical effect and tells us about the gems that are most likely to display it.

Read more


Hidden Treasures: Highlights of Gem-A's Gemstones and Minerals Collection

Hidden Treasures: Highlights of Gem-A's Gemstones and Minerals Collection

Gem-A Gemmology Tutor Pat Daly FGA DGA offers us a glimpse at some of the more unusual items in Gem-A's Gemstones and Minerals Collection.

Read more


Tanzanite: The Contemporary December Birthstone

Tanzanite: The Contemporary December Birthstone

Are you looking for the perfect festive gift for a December baby? Gem-A tutor Lily Faber FGA DGA EG considers tanzanite – one of three birthstones for December – and shares how this relatively new gemstone compares to its purple and blue-hued rivals.

Read more


Birthstone Guide: Turquoise For Those Born In December

Birthstone Guide: Turquoise For Those Born In December

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...

Read more


Understanding the Cat's Eye Effect in Gemstones

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 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.

Read more


Jade and its Importance in China

Jade and its Importance in China

Jade has long been revered by gem lovers internationally, but nowhere more so than in China. But what is it that makes this gemstone so special? Gem-A's Assistant Gemmology Tutor Dr Juliette Hibou FGA gives us an overview of jade, how to identify it and its significance in Chinese culture.

Read more


Highlights of Gem-A Conference 2019

Highlights of Gem-A Conference 2019

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!

Read more


 

Additional Info

Read more...

Leading the World's First Gemstone Testing Laboratory: Gem-A's Basil Anderson

As we build up to the Gem-A Conference 2018 in November, we are continuing our celebration of the Gem-A Greats who have been pivotal in our history. This week’s Heritage Series turns to another of Gem-A’s founding fathers, Basil Anderson.

Basil Anderson with X-ray equipment. Image Credit Gem-A.

At a time when the gemmological world and the jewellery industry were rapidly changing with new innovations and the appearance of sophisticated synthetics, Basil Anderson was a pivotal figure in ensuring the link between gemmological science and industry-practice. His commitment to maintaining the important relationship between gemmologist and jeweller is still at the heart of Gem-A’s educational ethos to this day.

READ MORE: Heritage Series, Dr Herbert Smith 

Educated at Kings College London, Anderson graduated with a first class degree in Chemistry and Mineralogy in 1924. That same year he was introduced via his professors to Mr Tanburn of Hatton Garden, who was actively looking for someone to run the world’s first gemstone testing laboratory.


Original Notes from Anderson's colleague CJ Payne at the Testing Laboratory. Image Credit Gem-A

This was a critical time for the gemstone and pearl industry. With innovations such as Mikimoto’s development of cultured pearls in 1921, the jewellery industry was in a transitional period as it responded to the impact of synthetics on the industry.

In direct response to this new crisis, the London Chamber of Commerce created the ‘Diamond, Pearl and Precious Stone Trade Branch’ – with the aim of creating a laboratory to authenticate gemstones and pearls. The recently graduated Basil Anderson, much to his own humble surprise, was the ideal candidate, and in his 1981 lecture to Gem-A he recounted how he ‘toddled along’ to Hatton Garden for his interview. It is safe to say Anderson was successful, and following an all-important cup of tea, he began running the world’s first gemstone testing laboratory.

Collection of Anderson's Laboratory Notes from 1925. Image Credit ©Gem-A.

For Anderson, the jewellery sector was a “very ancient trade and it has always been a very honourable trade”, and the appearance of mass synthetics was “innocuous” because the chain of confidence – from miners to dealers to lapidaries to manufacturers to retailers – was shaken by the introduction of synthetics.

READ MORE: Birthstone Guide, Spinel for those born in August

So while Gem-A was created out of a need to provide gemmological education for the jewellery trade in 1908, the first gemstone testing laboratory was likewise created out of the need for gemmological knowledge and scientific authentication to safeguard integrity.


Original and latest editions of Anderson's Gem Testing.

Indeed, the very title of his 1942 book Gem Testing for Jewellers crystallises Gem-A’s ethos of providing gemmological knowledge to support jewellers, and of expanding gemmological science to reach jewellers, traders and the developing gemmological community. In the book’s original preface, Anderson stated it was intended “to reinforce the invaluable knowledge which the jeweller has gathered by virtue of long experience, to reinforce this knowledge by making it more conscious and giving it a firmer factual basis”.

READ MORE: Journal Digest, Rainbow Lattice Sunstone 


The Chelsea Filter, patented by Gem-A

LEGACY
Anderson ran the testing laboratory from 1924-79 and soon became the preeminent expert on pearl authentication of his day. While teaching Gem-A’s Gemmology Diploma, Anderson invented the Chelsea Colour Filter in 1934 with his colleague CJ Payne and the students at Chelsea Polytechnic, which is still sold today by Gem-A Instruments and used worldwide.

Early Advert for the Chelsea Colour Filter

Anderson became our head examiner 1951, succeeding Dr Herbert Smith, and was later voted in as Vice President in 1976.

READ MORE: Gem Empathy IJL Competition 2018

Anderson understood and advocated the importance of science and experience working together to the benefit of all in the gemmological and jewellery industry, so that traders were not hazarding opinions but could make informed factual analysis. Basil Anderson’s legacy to Gem-A can be seen in the laboratory named for him at Gem-A HQ in London, and in the annual awards in his honour at Gem-A graduation: the Anderson Medal, awarded for the best set of papers on the Foundation examination, and the Anderson/Bank prize for the best Gemmology Diploma theory paper. In 2013, Anderson was named in the French Association of Gemmology’s 50 most influential gemmologists of all time.


Basil Anderson, Image Credit Gem-A

As we look forward to the Gem-A Conference and Graduation this November, those graduates who are awarded the Anderson medals become a part of our proud history, together with our founders who helped to shape the gemmological world of today. 

If you would like to join us in celebrating 110 years of gemmology education click here and register for the Gem-A Conference 2018.

If you are a Gem-A Member or Student you will have received an email to book member or student rates, if you haven't received it please contact membership@gem-a.com.

Cover Image: Photographs of Basil Anderson in the Gem-A collection. Image Credit Gem-A


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.

Read more


Birthstone Guide: Garnet For Those Born In January

Birthstone Guide: Garnet For Those Born In January

If you're lucky enough to be born in January, vibrant garnet is your birthstone. A rainbow jewel of the gem world, garnet displays the greatest variety of colour of any mineral and is very often untreated, making it a rarity in the gem world. 

Read more


Getting Started with Quartz Inclusions

Getting Started with Quartz Inclusions

Do you know your calcite inclusions from your dumortierite, epidote, fluorite and rutile? Here, Charles Bexfield FGA DGA EG explores some incredible quartz inclusions and explains what to look for when shopping for quartz specimens.

Read more


Understanding Iridescence: Opals, Pearls, Moonstones and Fractured Stones

Understanding Iridescence: Opals, Pearls, Moonstones and Fractured Stones

Iridescence has to be one of the most mesmerising and magical optical effects seen in gemstones. But have you ever wondered how it occurs? Gem-A's Collection Curator Barbara Kolator FGA DGA shines a light on this fascinating optical effect and tells us about the gems that are most likely to display it.

Read more


Hidden Treasures: Highlights of Gem-A's Gemstones and Minerals Collection

Hidden Treasures: Highlights of Gem-A's Gemstones and Minerals Collection

Gem-A Gemmology Tutor Pat Daly FGA DGA offers us a glimpse at some of the more unusual items in Gem-A's Gemstones and Minerals Collection.

Read more


Tanzanite: The Contemporary December Birthstone

Tanzanite: The Contemporary December Birthstone

Are you looking for the perfect festive gift for a December baby? Gem-A tutor Lily Faber FGA DGA EG considers tanzanite – one of three birthstones for December – and shares how this relatively new gemstone compares to its purple and blue-hued rivals.

Read more


Birthstone Guide: Turquoise For Those Born In December

Birthstone Guide: Turquoise For Those Born In December

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...

Read more


Understanding the Cat's Eye Effect in Gemstones

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 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.

Read more


Jade and its Importance in China

Jade and its Importance in China

Jade has long been revered by gem lovers internationally, but nowhere more so than in China. But what is it that makes this gemstone so special? Gem-A's Assistant Gemmology Tutor Dr Juliette Hibou FGA gives us an overview of jade, how to identify it and its significance in Chinese culture.

Read more


Highlights of Gem-A Conference 2019

Highlights of Gem-A Conference 2019

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!

Read more


 

Additional Info

Read more...

Heritage Series: The Trailblazing Efforts of Robert Webster

Our Heritage Series celebrates some of the most prominent figures in Gem-A's History who have helped to shape the world of gemmology today. Listed in the French Association of Gemmology's '50 Most Influential Gemmologists of All-Time', this instalment turns to Gem-A's most prolific writer: Robert Webster.  

Born in 1899, the young Robert Webster left school at the age of 15 to support his widowed mother, and his father’s footsteps as a pawnbroker. As Basil Anderson notes in his touching obituary to Webster, this proved to be a valuable training ground for the practical gemmologist.


Webster and his Gemmology Class © Gem-A

During the First World War, Webster was awarded the Military Medal for his bravery in carrying messages under fire, and on returning to England he began studying gemmology at Chelsea Polytechnic under Mr I.G Jardine. It was here in 1933 that Webster met the recently appointed lecturer in gemmology, Basil Anderson, at a time when the gemmological world was, in Anderson’s own words, “advancing on all fronts”.

Webster soon became a regular contributor to The Gemmologist (predecessor to The Journal of Gemmology) specialising particularly in ivory, and he secured his Gemmology Diploma a year later in 1934.


Early Articles by Webster.

Robert Webster’s gemmological career went from strength to strength: in 1942 he became an assistant lecturer at Chelsea Polytechnic and, following WWII, he was invited by Basil Anderson to join the Testing Laboratory team in Hatton Garden, to tackle the new challenge of calibré synthetic corundum. In the first year alone they tested 105,000 stones!

In the 1940s the Gemmological Association established the Research Diploma, to encourage and recognise excellent postgraduate research by Fellows of the Association. Robert Webster is one of only six people to be awarded this coveted Diploma for his thesis on ivory and its various imitations. It made such an impact that renowned mineralogist Dr Herbert Smith added sixteen pages to his 1949 revision of Gemstones!

Collection of Editions of Webster's Compendium, with document from Annual Report of the testing lab for the London Chamber of Commerce

In 1937 Webster published his Gemmologists’ Pocket Compendium with “the intention to cover as concisely as possible all the information most useful to the practical gemmologist”. This captured the spirit of Gem-A’s ethos since 1908 of providing quality gemmological education for the benefit of the gems and jewellery industry, and was built on the very data recorded by Basil Anderson and C.J Payne, the compendium has been the ‘bible’ of professional and amateur gemmologists and retail jewellers.

Together with his 1941 Practical Gemmology and epic two-volumed Gems in 1962, Webster’s contribution to gemmological research has made him one of the most recognised voices in Gem-A history. His prolific work is still held in high esteem, to such an extent that when contributors were invited to revise Gems, gemmologists from Australia, Canada, Germany, Thailand, Vietnam, the UK and the USA answered the call.

Robert Webster © Gem-A.

On Webster’s death at the age of 77 in 1976, Anderson’s touching tribute to his friend’s memory serves as a testament to Webster’s impact on the gemmological world:

"So manifold and varied were the activities of Robert Webster in the field of gemmology that the gap left in our ranks by this death can never adequately be filled – not, at least, by any one person."

Robert Webster is remembered at Gem-A as one of our greatest gemmologists. Future gemmologists studying at Gem-A HQ in London are taught in the Webster Room, dedicated to his memory. To this day, Webster’s Gemmologists’ Compendium remains one of the most comprehensive guides for anyone studying gemmology. 

If you would like to join us in celebrating 110 years of gemmology education click here and register for the Gem-A Conference 2018.

If you are a Gem-A Member or Student you will have received an email to book member or student rates, if you haven't received it please contact membership@gem-a.com.

Cover Image: Photograph of Robert Webster from the Gem-A collection. Image Credit Gem-A


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.

Read more


Birthstone Guide: Garnet For Those Born In January

Birthstone Guide: Garnet For Those Born In January

If you're lucky enough to be born in January, vibrant garnet is your birthstone. A rainbow jewel of the gem world, garnet displays the greatest variety of colour of any mineral and is very often untreated, making it a rarity in the gem world. 

Read more


Getting Started with Quartz Inclusions

Getting Started with Quartz Inclusions

Do you know your calcite inclusions from your dumortierite, epidote, fluorite and rutile? Here, Charles Bexfield FGA DGA EG explores some incredible quartz inclusions and explains what to look for when shopping for quartz specimens.

Read more


Understanding Iridescence: Opals, Pearls, Moonstones and Fractured Stones

Understanding Iridescence: Opals, Pearls, Moonstones and Fractured Stones

Iridescence has to be one of the most mesmerising and magical optical effects seen in gemstones. But have you ever wondered how it occurs? Gem-A's Collection Curator Barbara Kolator FGA DGA shines a light on this fascinating optical effect and tells us about the gems that are most likely to display it.

Read more


Hidden Treasures: Highlights of Gem-A's Gemstones and Minerals Collection

Hidden Treasures: Highlights of Gem-A's Gemstones and Minerals Collection

Gem-A Gemmology Tutor Pat Daly FGA DGA offers us a glimpse at some of the more unusual items in Gem-A's Gemstones and Minerals Collection.

Read more


Tanzanite: The Contemporary December Birthstone

Tanzanite: The Contemporary December Birthstone

Are you looking for the perfect festive gift for a December baby? Gem-A tutor Lily Faber FGA DGA EG considers tanzanite – one of three birthstones for December – and shares how this relatively new gemstone compares to its purple and blue-hued rivals.

Read more


Birthstone Guide: Turquoise For Those Born In December

Birthstone Guide: Turquoise For Those Born In December

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...

Read more


Understanding the Cat's Eye Effect in Gemstones

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 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.

Read more


Jade and its Importance in China

Jade and its Importance in China

Jade has long been revered by gem lovers internationally, but nowhere more so than in China. But what is it that makes this gemstone so special? Gem-A's Assistant Gemmology Tutor Dr Juliette Hibou FGA gives us an overview of jade, how to identify it and its significance in Chinese culture.

Read more


Highlights of Gem-A Conference 2019

Highlights of Gem-A Conference 2019

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!

Read more


 

Additional Info

Read more...

Heritage Series: Sir James Walton, The Royal Surgeon

If you have had the chance to visit us here at Gem-A HQ, you may have had the opportunity to see the Sir James Walton Library, which is one of the largest collection of gemmological books in Europe and holds some of the greatest works in gemmological science, including Walton’s Practical Gemmology. But did you know that for the majority of his life Walton was a decorated medical professional and a surgeon to royalty?  

Sir James Walton was the President of the National Association of Goldsmiths 1953-55 and served as the Gemmological Association’s Chairman in 1955, following a long illustrious medical career. Walton was awarded the Fellowship of the Royal Colleges of Surgeons among his many qualifications, and was established both as an Officier de la Legion d’Honneur, and a Knight Commander of the Royal Victorian Order (K.C.V.O) which recognises personal service to a reigning monarch of the United Kingdom.


Sir James Walton

READ MORE: Heritage Series: The Trailblazing Efforts of Robert Webster

Born in 1881, James Walton was elected to the staff of the London Hospital in 1913, where he worked for 33 years. During the First World War, Walton was a Captain in the Royal Army Medical Corps (RAMC). Walton was stationed at the 2nd London General Hospital and served as a surgeon to the Empire Hospital specialising in diseases of the brain and spinal cord, and in WWII he was a Brigadier in the Army Medical Department.

In 1930, Walton was also appointed as surgeon to the Royal Household of King George V, and served through both his reign and those of his sons Edward VIII and George VI, until 1949. During his dedicated service he was official surgeon to Queen Mary from 1936-49, and it was through their shared enthusiasm for gemmology that Queen Mary honoured the Association by visiting the Gemmological Association’s Exhibition in 1951 at Goldsmiths’ Hall.

Queen Mary, Sir James Walton, and President Dr Herbert Smith
at the 1951 Gemmological Association Exhibition


Dedication in Walton's Practical Gemmology

READ MORE: Speaker in the Spotlight: Q&A with Dr Eloïse Gaillou

After an illustrious career, serving as President of the Association of Surgeons and the Medical Society of London respectively, Walton began his well-earned retirement in 1946, where he entered the fascinating world of gemmology.

While his investigation of gemstones was an enjoyable hobby, by Walton’s very nature this hobby developed into an intensive and specialised study. Despite not having the traditional background of most gemmologists, Walton mastered the subject of Crystallography and became a recognised authority on precious stones in the UK, accumulating in his book Practical Gemmology.


Dedications to B.W. Anderson and to Dr Herbert Smith by Sir James Walton in his 'Practical Gemmology'

Described by Robert Webster as ‘a valuable contribution to gemmology’ (JoG 1953 Vol.4.No.1), Walton’s book addressed an important gap: he had noticed that there was not a book aimed at the new or amateur gemmologist who did not have (or necessarily need) a scientific or geological background:

‘The majority of books are written in technical language and are interspersed with many mathematical proofs and equations from which they [non-specialists/hobbyists] shrink with aversion if not with horror.’

Walton aimed to gather ‘an account of the scientific principles upon which the subject of mineralogy is based’ but to ‘divest it as far as possible of all mathematical considerations, to present it in the simplest non-technical language…so that it may be of easy understanding even to those devoid of all scientific knowledge.’

READ MORE: Leading the World's First Gemstone Testing Laboratory: Gem-A's Basil Anderson

That being said, Walton’s book is of incredible scientific value, and included unpublished material by Basil Anderson and CJ Payne, who supported this important project that created an essential book for those who approached gemmology out of inquisitive enthusiasm. In 1947 Walton was also appointed the first curator of the Association’s collection of gemstones.  


Sir James Walton

Upon his death in 1955, a vast collection of Sir James Walton’s books and stones were generously bequeathed to the Association, and are now housed in the Sir James Walton library at Gem-A HQ London. So when you next visit us at Ely Place, please ask to visit our exquisite library and immerse yourself in a part of Gem-A history and Walton’s living legacy.


The Sir James Walton Library at Gem-A HQ London

If you would like to join us in celebrating 110 years of gemmology education click here and register for the Gem-A Conference 2018.
If you are a Gem-A Member or Student you will have received an email to book member or student rates, if you haven't received it please contact membership@gem-a.com.

Cover Image: Photograph of Sir James Walton from the Gem-A collection. All Image Credits: Gem-A.


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.

Read more


Birthstone Guide: Garnet For Those Born In January

Birthstone Guide: Garnet For Those Born In January

If you're lucky enough to be born in January, vibrant garnet is your birthstone. A rainbow jewel of the gem world, garnet displays the greatest variety of colour of any mineral and is very often untreated, making it a rarity in the gem world. 

Read more


Getting Started with Quartz Inclusions

Getting Started with Quartz Inclusions

Do you know your calcite inclusions from your dumortierite, epidote, fluorite and rutile? Here, Charles Bexfield FGA DGA EG explores some incredible quartz inclusions and explains what to look for when shopping for quartz specimens.

Read more


Understanding Iridescence: Opals, Pearls, Moonstones and Fractured Stones

Understanding Iridescence: Opals, Pearls, Moonstones and Fractured Stones

Iridescence has to be one of the most mesmerising and magical optical effects seen in gemstones. But have you ever wondered how it occurs? Gem-A's Collection Curator Barbara Kolator FGA DGA shines a light on this fascinating optical effect and tells us about the gems that are most likely to display it.

Read more


Hidden Treasures: Highlights of Gem-A's Gemstones and Minerals Collection

Hidden Treasures: Highlights of Gem-A's Gemstones and Minerals Collection

Gem-A Gemmology Tutor Pat Daly FGA DGA offers us a glimpse at some of the more unusual items in Gem-A's Gemstones and Minerals Collection.

Read more


Tanzanite: The Contemporary December Birthstone

Tanzanite: The Contemporary December Birthstone

Are you looking for the perfect festive gift for a December baby? Gem-A tutor Lily Faber FGA DGA EG considers tanzanite – one of three birthstones for December – and shares how this relatively new gemstone compares to its purple and blue-hued rivals.

Read more


Birthstone Guide: Turquoise For Those Born In December

Birthstone Guide: Turquoise For Those Born In December

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...

Read more


Understanding the Cat's Eye Effect in Gemstones

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 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.

Read more


Jade and its Importance in China

Jade and its Importance in China

Jade has long been revered by gem lovers internationally, but nowhere more so than in China. But what is it that makes this gemstone so special? Gem-A's Assistant Gemmology Tutor Dr Juliette Hibou FGA gives us an overview of jade, how to identify it and its significance in Chinese culture.

Read more


Highlights of Gem-A Conference 2019

Highlights of Gem-A Conference 2019

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!

Read more


 

Additional Info

Read more...

Heritage Series: Let's Bragg About It! Our Nobel Prize Winning Presidents

Did you know that two of Gem-A’s presidents were actually Nobel Prize Winners? Sir William Henry Bragg, the Association’s president 1937-42, and his son Sir Lawrence Bragg president 1954-72, were jointly awarded the Nobel Prize for Physics in 1915 for their research in X-ray Crystallography – an epic achievement that laid the foundation for future scientific breakthroughs and the basis of 26 other Nobel Prize winners and counting!

William Henry Bragg (WHB) had an exceptional mind, winning a Minor Scholarship to Trinity College, Cambridge, at the age of 17! The family considered this a bit too young, so a year later in 1881 WHB began the Mathematical Tripos at Trinity, and after graduating he began research at Cambridge’s Cavendish Laboratory to train in physics.

Sir William Henry Bragg. Image Credit: Gem-A.

In 1886, at the age of 23, he was appointed the Elder Professor of Mathematics and Experimental Physics at the University of Adelaide. Much of his time was taken with teaching commitments, leaving little room for research, but WHB maintained his interest in physics and kept up to speed with the latest developments by Prof. Wilhelm Röntgen at Würzburg, Germany, who had discovered an exciting new form of radiation, ‘so mysterious that he called it the X-ray’ (Hunter 2004: 6-8). At 41, WHB began to explore X-ray radiation, winning international recognition and was nominated to the Royal Society in 1907, and took the Cavendish Chair in Physics at Leeds, England in 1909.

Bragg’s first son, William Lawrence (WLB), was born in 1890 and later recalled that his father would tell his sons bedtime stories about the properties of atoms “We started with hydrogen and ran through a good part of the periodic table.” (Hunter 2004: 8; RI, MS WLB pp8-12).  Equally brilliant, WLB entered the University of Adelaide a year early at the age of 15 and achieved a First Class Hons in mathematics. When the family moved to England, WLB, like his father before him, entered Trinity College Cambridge, but switched from mathematics to physics.

Sir William Lawrence Bragg.
Image Courtesy of the Royal Institution of Great Britain.

WHB was aware of the recent Munich Experiment of 1912 where Max von Laue, Walter Friedrich and Paul Knipping targeted sphalerite crystals with X-ray beams, backed with a photographic plate to track the diffraction pattern. Today, gemmologists are quite familiar with diffraction patterns from X-ray spectroscopy, however, it is important to remember that at this time, scientists were still establishing the nature of X-rays, whether we were talking about waves or atom particles, and WHB was still yet to invent the first X-ray spectrometer:

"Nothing was certain then, X-rays were mysterious"
 Prof. André Authier, Université Piérre et Marie Curie.

It was the 22 year old WLB who fully realised the ramifications of Laue’s epic discovery that X-rays were diffracted by the crystal structure: he established the relationship between the wavelength of radiation, angles of incidence and diffraction, and the spacing of layers of atoms in a crystal structure. Knowing the first two, the third could be calculated. This became known as Bragg’s Law:

n λ = 2d sin θ

d being the distance between atoms by using geometry

This leap of genius was the key to measuring and understanding atomic structures, which could only be inferred up to that time. As he later said in his 1959 lecture to the Royal Institution:

"What is it, really, that makes a thing a crystal? It is it’s inside arrangement, it’s the fact that the molecules or atoms in it are an absolutely regular pattern, like soldiers on parade."


Crystallography in the Sir James Walton Library at Gem-A HQ. 

To facilitate this his father WHB designed the X-ray spectrometer:
"It contained a platform on which the crystal could be rotated with respect to the X-ray beam and an ionisation chamber that could be rotated around the crystal. The ionisation chamber contained a gas that was ionised by X-rays and an electrometer so that the amount of radiation detected could be qualified." (Hunter 2004: 35)

The impact of the Braggs’ research – and Bragg’s Law – cannot be overemphasised:

"it could be well argued that the scientific method of X-ray crystallography has been as great as those of quantum theory and relativity, and the impact on everyday life even greater." (Hunter 2004: xiii)

From this exciting realisation, father and son worked tirelessly over the Summers of 1913 and 1914, and in 1915 the younger Bragg received a telegram whilst on the Front in the First World War that he and his father had been awarded the Nobel Prize in Physics for their research in X-ray Crystallography.

This enshrined the Braggs into history.  Moreover, WLB was instrumental in supporting the British Expeditionary Force in France and Belgium in WWI by applying scientific sound ranging to locate enemy guns by sound.  In 1941 Bragg was a scientific liaison officer between Great Britain and Canada, and an advisor to the British Navy on antisubmarine work, and sat on the advisory council to the Minister of Supply.

Publications in the Sir James Walton Library at Gem-A HQ. 

Over the course of their careers both father and son were heavily involved with the scientific community at the Manchester Laboratory, the Cavendish Laboratory, and the Davy-Faraday Laboratory at the Royal Institution of Great Britain. Indeed, both Braggs were in turn appointed Resident Professor at the Royal Institution, and both served as Presidents of the Gemmological Association – a link that is revived again this year when we return to the Royal Institution for our Graduation, 80 years since William Henry Bragg presented awards to our graduates.

In his inaugural address WHB noted his honour at being our President:

Your Association has paid me a great honour in asking me to be your President…you must allow me to begin by address this evening by expressing my warm appreciation… I have of course no inner knowledge of your ancient, beautiful and wonderful craft and feel flattered that you have invited me, a physicist, whose concern in precious stones differs so much from that of the craftsman, to be associated with you in this honourable way… If, apart from their use as precious stones, crystals were regarded at one time as mere curiosities, the situation is entirely changed. We have learnt that the crystalline structure is one of the great orders of Nature, occurring everywhere and not merely in the rare specimen… I suppose that the jeweller looks to the diamond as the king of gems. To the physicist, the internal structure of the diamond is of extraordinary interest for its strong and beautiful simplicity and for the information which it gives as to the properties of the carbon atom. For the diamond consists of carbon alone, and the bonding facilities of the carbon atom are directly exhibited.  

Indeed, in keeping with the Basil Anderson's gemstone testing laboratory, WHB noted the importance of X-ray crystallography to the gemmologist, as it "gives you a means, if you need it, of deciding between the true and the false."

In 1954, Sir Lawrence Bragg was extended the same invitation to become our President. In his address, WLB appreciated the honour as both his father and their close friend, Sir Henry Miers, had both served the Association in this way. Just as we were created as a means to provide gemmological education to the wider jewellery industry, WLB firmly believed that scientists had a duty to share their knowledge:

"There is one sense, however, in which the pure scientist is, in my opinion, deeply wrong in withdrawing into his ivory castle.
He must pursue knowledge for its own sake,but at the same time it is his duty to see that
this knowledge is so digested, arranged, and simplified that it can become a possession of all those who desire to attain it."

It is fitting, then, that in 2018 we will be celebrating our Gemmology Diploma and Diamond Diploma Graduates at the Royal Institution on November 5, celebrating 110 years of creating gemmologists worldwide.

The Royal Institution of Great Britain. Image Credit: SB Gem-A.

If you would like to join us in celebrating 110 years of gemmology education click here and register for the Gem-A Conference 2018.

If you are a Gem-A Member or Student you will have received an email to book member or student rates, if you haven't received it please contact membership@gem-a.com.

Cover Image: Sir Lawrence Bragg, Courtesy of the Royal Institution of Great Britain. 


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.

Read more


Birthstone Guide: Garnet For Those Born In January

Birthstone Guide: Garnet For Those Born In January

If you're lucky enough to be born in January, vibrant garnet is your birthstone. A rainbow jewel of the gem world, garnet displays the greatest variety of colour of any mineral and is very often untreated, making it a rarity in the gem world. 

Read more


Getting Started with Quartz Inclusions

Getting Started with Quartz Inclusions

Do you know your calcite inclusions from your dumortierite, epidote, fluorite and rutile? Here, Charles Bexfield FGA DGA EG explores some incredible quartz inclusions and explains what to look for when shopping for quartz specimens.

Read more


Understanding Iridescence: Opals, Pearls, Moonstones and Fractured Stones

Understanding Iridescence: Opals, Pearls, Moonstones and Fractured Stones

Iridescence has to be one of the most mesmerising and magical optical effects seen in gemstones. But have you ever wondered how it occurs? Gem-A's Collection Curator Barbara Kolator FGA DGA shines a light on this fascinating optical effect and tells us about the gems that are most likely to display it.

Read more


Hidden Treasures: Highlights of Gem-A's Gemstones and Minerals Collection

Hidden Treasures: Highlights of Gem-A's Gemstones and Minerals Collection

Gem-A Gemmology Tutor Pat Daly FGA DGA offers us a glimpse at some of the more unusual items in Gem-A's Gemstones and Minerals Collection.

Read more


Tanzanite: The Contemporary December Birthstone

Tanzanite: The Contemporary December Birthstone

Are you looking for the perfect festive gift for a December baby? Gem-A tutor Lily Faber FGA DGA EG considers tanzanite – one of three birthstones for December – and shares how this relatively new gemstone compares to its purple and blue-hued rivals.

Read more


Birthstone Guide: Turquoise For Those Born In December

Birthstone Guide: Turquoise For Those Born In December

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...

Read more


Understanding the Cat's Eye Effect in Gemstones

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 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.

Read more


Jade and its Importance in China

Jade and its Importance in China

Jade has long been revered by gem lovers internationally, but nowhere more so than in China. But what is it that makes this gemstone so special? Gem-A's Assistant Gemmology Tutor Dr Juliette Hibou FGA gives us an overview of jade, how to identify it and its significance in Chinese culture.

Read more


Highlights of Gem-A Conference 2019

Highlights of Gem-A Conference 2019

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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Delving into Diamonds: Gem-A President and Diamond Expert, Eric Bruton

There is one name in gemmological science that is synonymous with the study of Diamonds: BRUTON. Studying under the genius of Basil Anderson and Robert Webster, Eric Bruton had such an impact on the gemmological world that his work forms the basis of Gem-A’s Diamond Diploma to this day.

Born in London in 1915, Bruton started a career in publishing before joining the engineering branch of the RAF during World War II, where he was in charge of technical training and also served in India.

Eric Bruton ©Gem-A

On returning to the UK, Bruton was invited to edit four prominent publications: Industrial Diamond Review, Horological Journal, Goldsmiths’ Journal and – importantly for Gem-A – The Gemmologist, published by the National Association of Goldsmiths (NAG). Bruton immediately signed up for classes at Chelsea Polytechnic – then being led by Anderson and Webster – and began what would become a life-changing adventure into the world of gemmology.

READ MORE: Speaker in the Spotlight, Peter Lyckberg

Eric Bruton was awarded his Gemmology Diploma in 1950, and began teaching for the Association in 1967 – specialising in diamonds, running courses at St John Cass College London, and a similar course at Barcelona University – with examinations by The Gemmological Association of Great Britain. All of this was building up to Bruton’s breakthrough publication, his first practical handbook in 1970: Diamonds.

Until Diamonds, books on this subject were either highly technical or focused on one particular aspect of the industry. Recognising this problem, Bruton’s response was to cover all aspects of gem diamonds, spanning the history of diamond, mining and recovery, cutting methods, grading and valuation, and the identification of diamond and its simulants.

READ MORE: Investigating Fake Rough 

Throughout his research and his travels to various diamond mines across the world, Bruton realised that the various compartments of the diamond industry had little – or indeed no – knowledge of their counterparts. Most important of all, members of the public did not ‘appreciate that the possession of a diamond…has taken 4000 years of endeavour – blood, toil, sweat and tears – to produce the modern brilliant-cut diamond’ (viii).

Bruton was the ideal person to address this – with his editorial experience and gemmological expertise, he was in a rare and strong position to deliver.

Eric Bruton by David Langdon, 1971. Image Credit: Gem-A. 

Bruton’s Diamonds is a systematic study of all aspects of diamonds and forms the foundation of Gem-A’s Diamond Diploma. For many years, Bruton specialised in writing on all matters relating to gems, jewellery, and watches – and  even crime fiction! Bruton also founded the trade’s only newspaper of the time – Retail Jeweller – which, in competition with Watchmaker Jeweller & Silversmith - became the voice of the trade, and in 1994 was elected president of the Association.

READ MORE: Heritage Series, Let's Bragg About It! 


Today, Bruton’s contribution to the Gem-A is remembered with the Bruton Medal, a prize awarded to exceptional students with the best results in the Diamond Diploma examination, and the Bruton Room at Gem-A HQ in London, where future gemmologists study diamonds.

Interested in finding out more about gemmology? Sign-up to one of Gem-A's courses or workshops.

If you would like to subscribe to Gems&Jewellery and The Journal of Gemmology please visit Membership.

Cover Image: Diamond Crystal Trigons, photo by Pat Daly, with Bruton Medal. Image by Gem-A. 


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Birthstone Guide: Garnet For Those Born In January

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Getting Started with Quartz Inclusions

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Do you know your calcite inclusions from your dumortierite, epidote, fluorite and rutile? Here, Charles Bexfield FGA DGA EG explores some incredible quartz inclusions and explains what to look for when shopping for quartz specimens.

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Understanding Iridescence: Opals, Pearls, Moonstones and Fractured Stones

Understanding Iridescence: Opals, Pearls, Moonstones and Fractured Stones

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Tanzanite: The Contemporary December Birthstone

Tanzanite: The Contemporary December Birthstone

Are you looking for the perfect festive gift for a December baby? Gem-A tutor Lily Faber FGA DGA EG considers tanzanite – one of three birthstones for December – and shares how this relatively new gemstone compares to its purple and blue-hued rivals.

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Birthstone Guide: Turquoise For Those Born In December

Birthstone Guide: Turquoise For Those Born In December

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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Understanding the Cat's Eye Effect in Gemstones

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 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.

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Jade and its Importance in China

Jade and its Importance in China

Jade has long been revered by gem lovers internationally, but nowhere more so than in China. But what is it that makes this gemstone so special? Gem-A's Assistant Gemmology Tutor Dr Juliette Hibou FGA gives us an overview of jade, how to identify it and its significance in Chinese culture.

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Highlights of Gem-A Conference 2019

Highlights of Gem-A Conference 2019

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!

Read more


 

Additional Info

Read more...
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