An Exclusive Interview with Gem Cutter John Dyer

Belinda Morris talks to renowned and much-admired lapidary John Dyer, one of the speakers at the 2016 Gem-A Conference, about the science and art of gem cutting. 

Did you train as a gemmologist or gem cutter?

I loved gems and business from an early age. I was also home-schooled and one of my parents’ strategies for teaching me was to purchase books on subjects I was interested in, so they bought books on gems and gemmology for me (Gem Identification Made Easy by Antoinette Matlins and Antonio C. Bonanno was one of the first) and that stoked my interest.

At 16 I wanted to start in the gem business and my dad said he would help me out. One thing led to another and we ended up going to Zambia to buy gemstones. We bought rough gems instead of cut ones to get a better deal and when we brought them back we took them to a cutter to have them cut. He did a really bad job on them and charged us a lot of money for it. 

This resulted in us getting mad and buying a faceting machine because, as my father said: “We can do that well, or better, ourselves, and cheaper too!” This all turned out to be a blessing in disguise because it helped us to discover that I love to cut gems. So although the gems we bought on that trip were not super profitable in the end, it started us in the direction of what has now become the focus of our business - high quality and creative gem-cutting. 

I never had any formal training. There were no lapidaries interested in teaching near me that I knew of, and as far as gemmology goes I mainly learned from books and practical experience. I would consider myself a far better cutter than gemmologist, but I do have certain practical, applicable gemmological techniques which help me when purchasing rough. Rough is almost easier to ID than cut gems, because you often still have the crystal habit, visible cleavage planes and more inclusions and other factors to help identify a gem and potential treatments it may have undergone. 

A 28.03 ct Citrine DreamscapeTM. Photo by John Dyer.
A 28.03 ct Citrine DreamscapeTM. Photo by John Dyer

Does the stone influence your design or do you choose the stone based on a particular cutting style that you want to see? 

The shape, colour and clarity of the rough are the main considerations in choosing the cut I am going to do. Usually I buy the best rough I can find and then cut to what I feel is best suited to it. There are times when I don’t buy a piece because I feel the shape and size it could cut would not have good marketable appeal, but other than that I pretty much let the rough dictate to me what it wants to be (that’s within certain limitations of marketability and visual appeal, of course). 

That challenge that each gem represents - trying to bring out its maximum potential - is one of the things I most enjoy about cutting. There are so many considerations that go into it and for the most part all those decisions are made on the fly as I saw and preform (pre-shape) the gem for dopping and faceting or carving. 

What is your favourite stone to work with and do you have a preferred design for it? 

My favourite gem to work with is aquamarine since it comes in reasonably large and clean gems, is easy to polish and has great transparency so it is well suited to a wide variety of different cutting styles. Also, since it isn’t dark, it shows the cut well instead of hiding it like some extra dark gems do. 

A 13.07 ct Aquamarine StarBrite TM. Photo by Lydia Dyer.
A 13.07 ct Aquamarine StarBriteTM. Photo by Lydia Dyer

There are sometimes cutting styles I prefer for specific gems; those with high dispersion (e.g. zircon) do better with flat faceted cuts than with concave facets or carving, since those tend to reduce the dispersion. Other gems with low dispersion I love to cut with concave facets or carving styles since they can increase the brilliance. It’s all part of the decision making process when deciding what to cut a specific piece or rough into. 

A 46.81 ct Aquamarine Super Trillion TM. Photo by John Dyer.
A 46.81 ct Aquamarine Super TrillionTM. Photo by John Dyer

You use many less well-known gemstones, do you find that this increases the public’s awareness of these stones, highlighting how beautiful they can be?

As far as using ‘less well-known’ gems go I find that the market is much more accepting of a wide range of gems than in the past. TV shopping has introduced many strange gem types to a large public audience and a certain percentage of that public has gone on to learn a lot about gems and become educated and sophisticated buyers. This, coupled with how expensive the ‘traditional’ gems have become, has really opened a wide door to the lesser known gems. 

That being said though, most of the gems I cut are still within the parameters of what is familiar to most jewellers - aquamarine, beryl, morganite, citrine, amethyst, ametrine, garnet of all kinds, sapphires, emerald, ruby, peridot, tourmaline (all colours), spinel and zircon make up most of my inventory.

Morganite StarBriteTM 50.92 ct cut by John Dyer & Co. Photo by Lydia Dyer.
Morganite StarBriteTM 50.92 ct cut by John Dyer & Co. Photo by Lydia Dyer

Sometimes I will do a very rare gem, such as bicolour spessartite, phenakite, oligoclase or similar, but they are the exception rather than the rule.

What do you endeavour to reveal in stones? 

Essentially what I am looking to reveal is the full potential for beauty that is in each piece of rough. So much labour goes into the searching for and mining of gem rough that I feel it should be cut in a manner that respects its true rarity and uniqueness. But at the same time some sacrifices of size and weight will need to be made for the gem to achieve its maximum beauty. That is the goal that I aim for. 

What do you look for when selecting a piece of rough? 

When selecting rough I look at the size, shape and clarity of each piece. I also take into account the value of the finished piece because there is a lot of labour involved in our cutting and if the finished value of the gem is too low we will not recoup our labour costs. For that reason there are some pieces of rough that are cool and pretty but I just can’t buy them because they won’t generate a profit. 

Do you travel to mines around the world to procure your own rough or do you often buy at shows? 

I have travelled to various countries in search of gems. My most valuable gem (my wife) is Brazilian from the state of Paraíba so the search has paid off! However, gems are often found in very small quantities and a trip direct to the mines can be a fruitless affair since there might not be any production for months at a time. This often results in my needing to buy from middlemen of some kind. Over the years we have formed relationships with a number of rough suppliers who bring us a variety of rough, that it would have been very hard to have access to on our own. After all, cutting is a time consuming business and if I spent all my time running about after rough I wouldn’t get much cutting done. 

Have you had any major cutting catastrophes? 

Major cutting catastrophes are something you like to put out of your mind, but there have been a number of them over the years. There was the kilo of pink tourmaline rough we heated without grinding clean first and broke almost all of it. There was a bixbite (red beryl) from Utah that cost us thousands of that we hoped to get over a carat’s worth of finished cut stone out of it, but it shattered due to internal stress and we ended up with three very small gems from it. There was the imperial topaz that I was carving and got too hot and broke it in half… and many other gems that have broken during carving, or been chipped or something similar. Over 20 plus years of cutting there are a lot of things like that which happen.

Talk us through the process of one of your famous cuts such as the Super Trillion™. What’s the process of cutting a gem in this way? How long does it take to cut some of your most famous designs?? 

The Super Trillion™ is all flat faceted and is an adaptation of a cut that was explained to me by Chris Remen (now deceased) which over time I tweaked to make a number of improvements to. The result is a semi-traditional looking trillion which I feel is super. Since it has so many facets it is very time-consuming to cut. How long it takes depends completely on the type of material and the size of the gem but it usually takes a day or longer to complete. 


A 26.11 ct Citrine Super TrillionTM. Photo by John Dyer.A 26.11 ct Citrine Super TrillionTM. Photo by John Dyer

Do you have any advice for people who want to take up lapidary? 

To take up lapidary as a hobby, the best thing to do is search for a local lapidary club. Often there will be retired members who will teach cutting for a very reasonable price and this often allows you to avoid the initial relatively high cost of the machinery and supplies. For those who want to make this a profession, I would recommend studying the market to be sure that it is really what they want to do… because it is not the easiest thing to make money at. 

You need to be a skilled cutter (something that often takes five years or more to accomplish) and make large investments in raw materials if you are going to sell your own gems. If you don’t sell your own gems, you are going to need to find a niche market for your cutting services and be very fast if you expect to make money because much of the gem trade is used to Asian pricing on gem cutting and that is hard to compete against until you educate your clientele about the difference in look and quality. That means a lot of outreach and marketing is involved. 

Rare red beryl (bixbite), cut by John Dyer & Co. Photo by Lydia Dyer.
Rare red beryl (bixbite), cut by John Dyer & Co. Photo by Lydia Dyer

You’ve won many awards for your work; which means the most to you? 

The award that means the most to me is the first place I took recently at the German Award for Jewellery and Precious Stones Idar-Oberstein 2015. This is one of my favourite competitions, but the fact that you have to adhere to a theme makes it more complicated. You might have a perfectly beautiful idea for a gemstone cut, but it must go with the theme to win. The theme in 2015 was ‘Light My Fire’, so I thought that an orange gem would fit well with the idea of fire. With this in mind, I searched through my stock of rough and selected a deep orange citrine, which, once ground clean, was a flame shape. Despite this it was still a challenge to decide what to do with the underside of the gem to make it look like fire. However, an idea came to me to execute a pattern that I had never done or seen before and which required an adaptation of my existing machinery and techniques - the result is a gem with a flame shape, but which also has little flame-shaped internal facets on the back which reflect light individually with varying intensities so that they look like flames shooting upwards as the gem is moved. 

John Dyer's flame-cut citrine, first place winner in the 2015 German Award for Jewellery and Precious Stones in Idar-Oberstein. Photo by Lichtblick Foto-Design, Hiltrud & Jurgen Cullmann of Schwollen, Germany.
John Dyer's flame-cut citrine, first place winner in the 2015 German Award for Jewellery and Precious
Stones in Idar-Oberstein. Photo by Lichtblick Foto-Design, Hiltrud & Jurgen Cullmann of Schwollen, Germany

Where do you see yourself going with your talent? What’s next for you in the lapidary world? 

It might not be super romantic, but I guess what I see is gradually improving what I already do and adding new styles and techniques to that. As a result of this I feel that each year our gems are better cut, more beautiful and more saleable. ■   

To view John Dyer's work click here

This article originally appeared in Gems&Jewellery Sept/Oct 2016 / Volume 25 / No. 5 pp. 28-32

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.


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

Birthstone Guide: Garnet For Those Born In January

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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.

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Understanding Iridescence: Opals, Pearls, Moonstones and Fractured Stones

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Tanzanite: The Contemporary December Birthstone

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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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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

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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Inside the World of Master Photomicrographer Danny Sanchez

Award-winning photographer Danny Sanchez GG, a speaker at the 2016 Gem-A Conference, reveals the secrets of photomicrography, the equipment he swears by and his favourite gemstones to photograph.

Q. What drew you towards photomicrography?

I was a working musician in Los Angeles and wanted a change of pace. I’d always loved gems and minerals and when I discovered that you could study them, their origins and applications, at the Gemological Institute of America, I couldn’t enrol quickly enough. The day I opened the course material and saw an inclusion photomicrograph, I was hooked.  

Q. What special equipment do you use?

I might be a little biased so I feel like a lot of my equipment is special. I think my most unusual piece of equipment is a vertical stepping rig that moves the microscope mere microns at a time.  

The home 'laboratory'
Danny Sanchez' home 'laboratory'

Q. Can you explain stacking for those that don’t know?

Microscopy deals in very narrow focal planes. A single photo has very little that is actually ‘in focus’. Focus stacking is a technique that allows one to merge multiple photos, each with different focal planes, into a single photo with greater depth of field. This is stacking. Using this technique, one is able to ‘manufacture’ depth. There is definitely a way to overuse stacking. Besides the visual residue that can be found in some photo ‘stacks’ (a group of photos merged into one), if a photo is rendered with too much depth, the viewer can lose perspective. Simply put, but somewhat counterintuitively, a photo with too much depth can look flat. 

A single photomicrograph play of colour in opal from Jalisco, Mexico. Field of view 3.05 mmThe complete stack of 81 photos. Field of view 3.05 mm

Left: A single photomicrograph play of colour in opal from Jalisco, Mexico. Field of view 3.05 mm. Right: The complete stack of 81 photos. Field of view 3.05 mm

Q. Do you look at images from earlier and wish you could retake some of the spectacular ones to add the ‘dimension’ it offers?

I definitely understand the impulse to go back and re-do a shot, but it’s not a strong one for me. I’m always trying to look forward, and to reproduce or re-tool an image I’ve already made seems like a step backward — particularly in light of how many dynamic subjects this industry offers. (For more information on stacking see Prince, N., ‘Use of Stacking Software for Expanding Depth-of-Field in Inclusion Photomicrography’, The Journal of Gemmology, 2014, 34(3), 188–89).  

Q. Do you have any advice for gemmologists wishing to try photomicrography at home?  

There are an overwhelming number of details to consider when trying to take a successful photograph through the microscope, and it’s hard to see the forest for the trees. The simplest recommendation I can make is: buy more light than is necessary. Gemmologists are used to using a specific type and amount of light during observation and imagine that will be sufficient when they sit down to take a photograph. It never is. Light is everything in photography; it’s even more important in photomicrography.  

Q. Do you have any particular favourite inclusions or gemstones to photograph?  

This past year I’ve immersed myself in opal with matrix. I have yet to find a mineral more dynamic that so readily yields actual landscapes. Part of what I look for in my own work is the feeling of being transported somewhere ‘other’. I enjoy the challenge of finding that in quartz or corundum, but when I work with opal in matrix, it’s almost like the photo takes itself.   

Opal from Magdalena. Jalisco, Mexico. Field of view 3.05 mm.
Opal from Magdalena. Jalisco, Mexico. Field of view 3.05 mm

Q. How do the public react to your photos? 

Most (non-gemmological) people don’t know what they’re looking at when standing in front of my photos. Once I tell them that it’s a photo of the inside of a gemstone, more often than not, they don’t believe me. Finally, when they do, they have a million questions. It’s really great to see people so invigorated about gems and minerals. I’m sure they’re much more interested when they leave than before they arrived. 

Ilmenite and hematite in orthoclase feldspar from Harts Range, Australia. Field of view 3.05 mm.
Ilmenite and hematite in orthoclase feldspar from Harts Range, Australia. Field of view 3.05 mm

Q. How do you source the stones that you work with? 

Mostly, I’ll buy at trade shows, looking through dealers’ back stock inventory — stones that, for one reason or another, have been passed over. Part of the joy of my process is these little discoveries and bringing something out of them that no one could have imagined. There’s something about owning the stones I work with (and hopefully producing an image from them) that makes the final product that much more satisfying. I’m not sure I can satisfactorily articulate why. Maybe, like every other gemmologist, I just like to hoard stones. 

Q. Do you see your photos as an educational tool or as an art form? 

Art is an inherently selfish act and mine is certainly no exception. All I ever wanted was to capture in my images a sense of mystery and wonder. It is purely self-serving and in this regard, it’s very ‘artsy’. But when people look at my images and discover that they are photos of actual minerals inside other minerals, there is an immediate spark of curiosity. The moment that happens, my photos become educational. 

Q. How long does it take you to capture the ‘magic’ shot? 

I’ll sit down with a parcel of stones and spend hours turning them over in my hands, changing the lighting environment, trying my best to disappear into the process. Once I’ve decided on which stone I’ll pursue, it could take another hour or so to test shoot dozens of lighting environments. The shooting and processing of a stack of 100 or more photos takes another 30 to 40 minutes. The real work happens over the following several days while I digitally develop the photo, just as I would if I were working in a traditional darkroom. 

Metal sulphide in fluorite, from Elmwood, Tennessee. Field of view 1.8 mm.
Metal sulphide in fluorite, from Elmwood, Tennessee. Field of view 1.8 mm

Q. What’s the most frustrating thing about photomicrography? 

The most frustrating thing is that I can’t do it for a living. My photos don’t have to be perfect, but they have to be representative of the view through my oculars, at the same time capturing the feeling of the moment of discovery. If I don’t feel I’ve done that after I’ve gone through the process of taking the shot(s) and developing the stack, it can be very frustrating. 

Q. What are your future plans for your work? 

Most of my work for the past few years has focused on atmosphere, the space within the stone and not any particular inclusion or the capturing of inclusions. That’s what interests me the most and that’s what I see myself pursuing; capturing and creating the space within gems. 

Q. If fleeing a burning building, what equipment do you grab?

Luckily for me, I’m not a photographer in the traditional sense of the word. I didn’t grow up aspiring to take photos nor did my penchant for gadgetry lean in that direction. My entry into the world of ‘prosumer’ cameras and lenses began with photomicrography. Because of this, I don’t have a collection of lenses or cameras that would make it hard to choose if fleeing a burning building. My most crucial pieces of equipment fit into one small hard case. I’m definitely fortunate in that regard. 

Q. Your studio improvisations suggest you have a good eye for engineering solutions to suit your needs…

Everything I have done, I’ve done on the shoulders of others. Of course, I’d like to think of myself as a tinkerer and problem solver but most of my equipment has existed in some form, on someone else’s desk, in someone else’s setup. It wasn’t easy piecing it all together but with help from a very small handful of people from around the globe, I’ve put together something that I’m really proud of. 

Q. Another big part of the job these days is software; how do you select the software you use? 

I’ve mentioned the stacking software and while that’s a tricky nuanced piece of software, it performs one function and is therefore finite in its ability to affect a photograph. Beyond that there is developing software such as Lightroom and Photoshop. Together, they can be used to alter an image in infinite ways. While they are indispensable tools, I try to remain as faithful to the view through my oculars as possible. 

Q. What are the ‘frontiers’ to be explored in photomicrography? 

I think the frontiers of photomicrography lay in the direction of software. We’re so lucky to be living in a time of amazing advances, in what computers can do to aid in our perception of the world around us. One day I hope to be able to pop on a pair of VR glasses and take a flight through a Kashmir sapphire or Mexican opal. 

Q. Do you have any gemmological heroes? 

Of course, Eduard Gübelin and John Koivula. Without their work, who knows where I’d be. 

Q. Who first encouraged you to be a photographer? 

In 2007, a year or so after I bought my first microscope, I was working at a trade show and was introduced to Edward Boehm. I already knew who he was, both in the trade and his family’s importance in gemmology. I shook his hand and told him, with no small amount of youthful hubris, that I was going to be a photomicrographer. He flashed me that great smile and told me to go for it. Every subsequent time I ran into him, he would always ask how it was going and if I’d made any progress with my photos. I was the smallest blip in his periphery but for the next five years he never forgot to ask about my photos. During that time I struggled with the pursuit itself and a lot of self-doubt. It wasn’t until 2013 that I was proud enough of my work to share it with the general public. His polite consideration was such a small gesture but it made me think: if this great gemmologist, grandson of the man who helped pioneer this field, hasn’t forgotten about me and my pursuit, I can’t forget either. ■   

To view more of Danny Sanchez's work click here or visit his Instagram @mineralien

This article originally appeared in Gems&Jewellery May/June 2016 / Volume 25 / No. 3 pp. 10-12

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 Opal, from Jalisco, Mexico. Field of view 3.05 mm. All images courtesy of Danny Sanchez. 


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


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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


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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


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Tanzanite: The Contemporary December Birthstone

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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...

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

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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

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An Interview with Dr Jeffrey Post of the Smithsonian Institution

Claire Mitchell FGA DGA talks to Dr Jeffrey Post, chairman of the Department of Mineral Sciences and curator of the National Gem and Mineral Collection at the Smithsonian Institution, about advanced gem testing, the Hope diamond and the importance of donations to the museum.

Dr Jeffrey Post with an assortment of beryls, a tanzanite and an amethyst. Interview with Dr Jeffrey Post.
Dr Jeffrey Post with an assortment of beryls, a tanzanite and an amethyst

Q. Moving forward, how important do you feel advanced testing will be?

I think it's getting there - a lot has changed in the last 10-15 years, particularly when you look at the kinds of sophisticated research instruments that the various gem labs have now. These days you’ve got pretty smart scientists out there trying to figure out ways to treat and enhance stones, so it takes pretty smart scientists and good instrumentation to be able to detect these treatments and enhancements. Nowadays there are labs all around the world that are treating stones - sometimes you don't find out about certain treatments until quite a bit later - so we are in an ‘arms race’ of sorts. It's getting to be fairly sophisticated material science - the kinds of techniques that are being applied are ones that are not always easy to detect, and ones that we would never have imagined that could be done. 

Read more: Getting to Grips with GemTOF Technology

I and many others have made the argument for a long time that we need well-trained scientists working in some of these labs, because the nature and sophistication of what is being done is dealing in the scientific. I think it’s a shame that there isn't a really clear path for someone to pursue research in science that will be directly relevant to gems. 

However, GIA - along with a couple of other groups - have tried to get together some funding to hire post-doctorates to work on gem-related projects, and have provided hands-on training to people that have good backgrounds in chemistry, physics and material science. It's clearly a step in the right direction - in the end you get someone who has that scientific background, but who also has some experience working on gem materials and who has been introduced to the gem world.

I think that the gem industry has some responsibility to try to help fund more of the kinds of research that needs to be done, research which will ultimately benefit the industry. Look at beryllium diffusion treatment, for example. That was something that no one ever expected - who would of thought of diffusing beryllium into corundum to change its colour - it's a pretty sophisticated treatment that took some research to figure out and understand, and then to develop a way to identify it. The trade were actually behind on that process by several years before it was finally cracked. 

It should be thought of as a much longer term investment - thinking about the health of the industry. For the good of all of us we need to figure out ways to be sure that we are staying up to date with technology, research and developments in related scientific fields. 

Q. The Smithsonian carried out advanced testing on the Hope diamond. It was reported that the type of instrumentation that was used created a very tiny hole in the diamond - did it? Was it hard to make the decision to test it in that way?

I hate to say it but it did. The key words here are that the hole was very, very, very tiny - if you look at it under a microscope you still can't see it. However, the decision to test in that way wasn't hard, not once I knew what the technique entailed. We had a pretty good understanding of what we were doing, what the test would involve and how the diamond would respond to it. We have a saying at the Smithsonian, that every specimen in the collection is available for research because ultimately, why are we keeping these things if we are not learning from them?

The Hope diamond is a very rare, blue diamond that is a piece of the earth. We use minerals and crystals to learn something about the earth - the Hope diamond has its own story to tell us about how it was formed, where it came from and how it is different from other diamonds, so I think that the fact that we have it in the collection means that it is available for us to study.

The Hope diamond in the Time-of-Flight-SIMS instrument. Image courtesy of Jeffrey Post. Interview
The Hope diamond in the Time-of-Flight-SIMS instrument. Image courtesy of Jeffrey Post

Read more: Harrods Unearths 228.31 ct Diamond from its Vaults for Private Sale

It wasn't just me it was a measured and thoroughly assessed decision. All the way through the tests we kept a close eye on things and made sure that it was working the way we thought it would, and so yes, we knocked a few billion atoms out of there, but no one is going to miss those few billion atoms. 

In the end we learned a fair bit of information about the diamond. We got a lot of publicity after we did that experiment and I think part of the reason for that was that people never thought about the Hope diamond as anything other than a ‘cursed’ gemstone worth a lot of money, so I think for many it was an eye-opener to think of it as something that is worth studying. The fact that it stays in the collection means that we can continue studying it.  

The instrument we use is the Time-of-Flight Secondary Ion Mass Spectrometer (ToF-SIMS) - 10-15 years ago we would never have imagined being able to use such an instrument or for somebody to have one in their department, so who knows, 10-15 years from now what other instrumentation will come along? What other options for testing will we have access to, that are equally non-destructive? It's therefore nice to know that we can go back and continue to try and pull a few little pieces of information from the item and continue to learn its secrets.  

Q. How important is the private sector to the purchase of acquisitions?

It's absolutely critical as the Smithsonian is a public-private partnership. We end up depending very heavily on private donations, particularly endowments that people have set up. Some of these go back 100 years whilst some of them are more recent, so one of our goals is that we are always trying to build up our endowments to continue to support the work that we do. 

Typically the collection has grown not from what we have purchased but from what people have given, so the big private partnerships are the donations that people have given us to help build the collection. Sometimes they come in as a large collection of minerals, sometimes as a single piece of jewellery or a single gemstone. The Smithsonian has been around for a long time (by USA standards, anyway) and so if we continue to accumulate at a steady rate the collection will grow to an even bigger collection. 

Read more: Last Chance to See the Record-Breaking Foxfire Diamond at the Smithsonian

Luckily we have time on our side; we don't need to get everything right away. One of the great parts of my job is the feeling that you are part of something that has had a long history and will have a long future - it's a cool feeling to be a part of something that has longevity associated with it. It gives you context for the work that you are doing and allows you to relax a little bit and say “I don't need to get that thing this year”, or “I don’t need to sell everything to get that one thing”, because that one thing, even if it goes into another collection now, will still be out there. 

The Dom Pedro Aquamarine, cut from a large crystal mined in Minas Gerais, Brazil. Cut by Bernd Munsteiner and donated by Jane Mitchell and Jeffrey Bland to the Smithsonian in 2011. Photo Credit Don Hurlbert. Image Courtesy of Smithsonian Institution.
The Dom Pedro Aquamarine, from Brazil. Cut by Bernd Munsteiner and donated by Jane Mitchell and Jeffrey Bland to the Smithsonian in 2011. Photo Credit Don Hurlbert. Image Courtesy of Smithsonian Institution.

It helps me to realise that my job never really had a beginning and doesn't really have an end; you are just stepping in as a caretaker of sorts, you keep things going and hopefully you will do some good things that will result in the collection growing.

As the National Museum of the USA we don’t charge, and so there really is a sense that people feel like the museum belongs to them - there is no better situation than one where you're saying “it's your museum, it's your collection, here's what we would like to do.” ■

The full version of this article originally appeared in Gems&Jewellery July/August 2016 / Volume 25 / No. 4 pp. 28-33

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 Smithsonian's National Museum of Natural History on the National Mall in Washington, D. C. Copyright Smithsonian Institution


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...

Gem Careers: A Lifetime of Expertise

Rosamond Clayton FGA DGA FIRV MAE, a gemstone specialist and jewellery valuer, is often called upon as an expert witness in trials to identify and value precious stones. 

When did you get started in gemmology?

I had been working in Hong Kong on a contract posting when I married in the 1970s and I needed to find a new and interesting career. Fortunately, my search for a fulfilling subject to study coincided with the arrival of Marcia Lanyon FGA in Hong Kong, whom I met at a friend’s house one evening. 

I was soon enrolled on a foundation gemmology course and quickly became a fanatic. Many in our trade will recognise this ‘disease’. When I visited China in 1973 for a business trip with my husband, we were each only allowed 15 pounds of luggage, including handbag and camera; Webster’s Gems formed part of this allowance! 

I took my foundation exams in Hong Kong in 1974 and passed, but it was diamonds that interested me and therefore I needed to study for the Diamond Diploma. I was helped by Noel Deeks FGA DGA who taught the practical diamond grading at Sir John Cass College in London, but there was nowhere to study in Hong Kong, so I partly commuted to London (subject to load on British Airways). Noel Deeks introduced me to a Mr Shun Wai Woo FGA DGA, the only DGA in Hong Kong at the time, who worked in a senior capacity with his cousin, who had started the only diamond manufacturing company there. 

In addition, through a friend, I was introduced to Bill and Joan Hsu who had studied the residential GIA diamond course in Santa Monica and returned to Hong Kong to run a diamond wholesale business. I went to their office at least once a week and graded all their stock; they taught me how to survive in business in Hong Kong. 

How did you transition to the world of valuations?

When Marcia Lanyon left Hong Kong she passed her consultancy work with the Hong Kong tourist association on to me, so by this time I knew most of the retailers. My boss at the time, a shrewd Chinese business woman, saw an opportunity to open up new accounts with these retailers. After three years I moved to a retailer in Kowloon on the mainland, called Tse Lee Yuen. 

Rosamond Clayton in Hong Kong, 1981. Image courtesy of Rosamond Clayton.
Rosamond Clayton in Hong Kong, 1981. 

One Monday I was instructed by my employer that I would become the valuer! I was to value all the customers’ diamonds and jadeite. My protests fell on ‘dead ears’ as I was told my English was better than my Chinese colleagues’ and the valuations had to be written in English – there were no typewriters with Chinese characters – therefore there was no argument. 

How did your own business evolve?

In 1985 I set up my own valuation business in Hong Kong, which I sold when I returned to the UK in 1987. Initially, on return to the UK, I rented space with jewellery designer John Donald at 120 Cheapside who I knew through Marcia Lanyon. It was a matter of going back to the start on the Monopoly board, only saved by the fact that the NAG and Gem-A were housed together in Carey Lane (in close proximity to Cheapside), and I was soon taken under the wing of Philip Stocker FGA the NAG in-house valuer. He introduced me to the Academy of Experts, who provide training for those taking instruction as expert witnesses. 

Have there been any memorable moments that really stand out?

I have always enjoyed travelling abroad for work and my most memorable business trip was for a Chinese friend, who was chairman of a marine diamond mining company in Namaqualand, looking at the possibility of cutting diamonds mined there in Hong Kong or New York, where he lived. 

My cousin was working as a commercial pilot in South West Africa (now Namibia), so I flew to Windhoek with a commercial airline and she flew me from Windhoek to the mine in a Beechcraft Bonanza. We stayed the night at Okiep near Springbok, about 500 miles from Windhoek and the next day to De Punt, North of the Oliphants River. 

Loughborough 2002 Valuer of the Year. Image by Vicky Morrison.
Loughborough 2002 Valuer of the Year. Image by Vicky Morrison.

In earlier times this river was much larger and brought the diamonds down, it is thought from Lesotho, exiting into the Atlantic and carrying the diamonds north with the current, in the same process as the Orange River at a later stage. Due to the rough sea conditions, the members of the mining franchises were only able to dive on average four times a year and I was fortunate to be there on one of these occasions. Apart from a substantial yield of fine quality diamonds they brought up crayfish for our evening barbecues. 

Can you tell us a little bit more about your profession and what makes it unique? 

I had been instructed as an expert in jewellery cases in Hong Kong and this work in the field of gemstones and jewellery had always held the greatest interest for me. Importantly, it is necessary to train to supply reports as an expert witness in court proceedings and it is now becoming a requirement by the courts, not merely a wise precaution. The cases are varied but the civil cases frequently involve post loss assessment, divorce or some aspect of alleged unethical trading. 

A case set down for a High Court hearing can last a number of years from the preliminary report to additional reports in light of new evidence, experts meetings and finally the hearing which can frequently last a week or a number of weeks. A great deal of research is required, sometimes many months just for one item. No other type of valuation work provides this opportunity. 

What would your advice be for anyone who wants to get into what you do? 

For aspiring valuers today it takes time to obtain the required qualifications and experience and the process may seem costly. However, it would be hard to find another field of interest with so many enthusiastic and generous people willing to give their time and knowledge. As a valuer, even once the initial qualifications are obtained, without the wealth of knowledge available and help from those in specialist fields, it would not be possible to operate. In addition there is not a moment to lose in grasping every opportunity for further knowledge and training in every aspect of our rich world. 

My own career in the field of gemstones and jewellery has been a long and challenging path and, at the outset, I had not entertained the idea of being a valuer but I believe that there has been a revolution in the methodology of jewellery valuing in the UK and I am proud to be a part of it.

Rosamond Clayton at the London Diamond Bourse in 2016. Image courtesy of Rosamond Clayton.
Rosamond Clayton at the London Diamond Bourse in 2016. 

Top Tips: Becoming a Valuer

Essential qualifications:

Gemmology, diamond grading, Certificate of Appraisal Theory (CAT - the NAJ’s self-learning programme on valuation methodology). Join the National Association of Jewellers Institute of Registered Valuers (NAJ IRV). 

Concurrently with obtaining qualifications:

Try to obtain experience with a diamond wholesaler, coloured stone wholesaler or manufacturer. 

Network:

It is impossible to operate even as an experienced valuer without contacts. Visit auction houses, museums, attend lectures and most importantly attend The NAJ Loughborough Conference where workshops and lectures are provided on every imaginable valuation topic. ■  

Gem-A members can log in to read the full article Gems&Jewellery Spring 2017 / Volume 26 / No. 1

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 Rosamond Clayton and her colleagues from the Institute of Registered Valuers. All images courtesy of Rosamond Clayton. 


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...

A Man of the Ocean: Diving for Organics with Eric Fritz

In a recent trip to the London headquarters, Eric Fritz, FDGA DGA manager of North America for Gem-A stopped by for an industry insider Q&A, educating us on theoretical and practical guidance of organic materials. Sarah Salmon speaks to the man of organic passion exploring the nature of these beautiful materials.

With a passion for pearls, a deep love for shells since the age of four and an extensive knowledge of coral, minerals and gemstones, Eric Fritz reveals his top tips when it comes to his specialty: organic gem materials.

Q. When identifying pearl, what are Gemmologists looking out for when grading their quality?

For value, you will be looking at whether it is a salt-water or freshwater pearl, whether it is natural - formed without any human involvement - or whether the pearl has been cultured. The most valuable in terms of quality across the board would be natural saltwater pearls. This would then be followed by natural freshwater pearls, saltwater cultured pearls to freshwater cultured pearls.

Roundness is also preferable when grading a pearl where the more perfectly round and larger it is without blemishes, the more precious it is considered. The bigger the pearl, provided it still has a good ‘roundness’ and lustre finish to it with minimal spots and blemishes to it, the more desirable and valuable it becomes.

Q. What causes the blemishes and imperfections to form on a pearl?

The blemishes are caused by the formation of the organic material itself. Formed by living organisms which, just like us are made up of a range of different imperfections, gives each pearl its unique, flawed composition. The living environment of the shellfish is also a key factor where surrounding waters may contain disease or the shell mechanism itself may malfunction; all of which directly affects the pearl quality.

Q. Where in the world are the most desirable pearls located?

Probably the most desirable and rarest natural pearl will always be the mellow mellow pearl. This is a yellow - golden range commonly found in Myanmar, Burma and Vietnam. The mellow mellow pearl is often hailed as the holy grail of all pearls due to being that of the most value.

The price of a pearl can vary widely in correlation to its size, ranging from $3000 to $65-70,000 at many Gem trade shows, even when such pearls contain blemishes and are therefore still considered imperfect

Q. We often hear about Mikimoto pearls, is this a particular brand or is it a type of organic pearl?

Mikimoto was the first person to commercially produce cultured pearls in Japan in the late 1800’s. Prior to this, cultured pearls had only been produced on an experimental basis but Mikimoto found a technique that he could use to sustainably produce small cultured pearls – typically 7mm - in small saltwater shells.

Its predecessors, being Gem-A, launched the first global Gem lab in London in order to differentiate cultured Mikimoto and natural pearls. The value of each was quite starkly different which meant that many London jewellers became concerned at the introduction of cultured pearls against the trade of more expensive natural pearls. Mikimoto, dating back over 100 years was, and probably still is, the top quality Japanese Akoya pearl on the market.

Q. Being similar in name, what is the key difference between a conch shell and a conch pearl?

Great question! The Conch shell, Lobatus Gigas being its scientific species, occurs only in the Caribbean off the coast of North America, from Florida down through to the West Indies. It is a big shell that was originally gathered by the native people for food due to its very large edible muscle. It is said that 1 in a hundred conch shells could produce a pearl. Conch pearls come in a range of colours from whites to pinks to browns and yellows but it is the pink variety that remains to be the most valuable. We often believe that the very inside of the Conch shell is pink in colour which is why the pink pearl remains the rarest.

However it is also the inside of the conch shell that produces all of the varying colours of conch pearls. Imitations are created when people take the conch shell and try and cut around a bead, passing it off as a genuine pearl. However, these imitations always have concentric bands where, if you look at the side of the bead, you will see what looks like tree ring growth around the edges. This is a kay indication that this is not a real pearl, but an imitation that has been cut out of a shell.

Q. With a huge variety on the market, how do you identify and compare different seashells from one another?

Seashells come in such a wide variety of genus, ranging from freshwater to seawater environments. Dating back to the Victorian times, seashells were and still are highly collectable objects of nature. Linnaeus, founder of the Linnaeus society extensively named over half of the shells we have identified so far. Seashells are very easy to tell the different species apart as they visually look very different from one another.

Today however to differentiate shells via its species level, identification can require DNA analysis to indicate the differences from one shell to the next. They may look very similar but there is stark variation between the different species.

Q. If you’re looking to purchase a high quality shell, what attribute should one be looking for?

People are attracted to different shapes and colour forms with some buying what we call ‘valves’ where two halves of a shell are held together by a muscle, whilst others favour gastropods where the shell is one piece. Some people like to collect a whole family of shells, preferring only to select pieces within the same genus of shells, leading to a lot of variability. Shell prices for collectors range from £2-£3 up to £100,000 for those that are highly desirable.

Q. What are the key differences between 'hard' and 'soft' coral?

A lot of the time when you look at soft corals in its natural habitat under water, they can often look like plants or sea fans which move with the ocean current. They can range in appearance from big broad fans to tall upright branches but most tend to move. Hard coral contains more calcium carbonate than soft and are often what we refer to as coral reef. An expansive garden of skeletons makes up the coral bed where tiny living organisms live within the pores of these hard corals.

Q. Where is Coral found in abundance across the world?

Coral is most commonly found within temperate waters, including the Caribbean, Australia and the Pacific, with its particular type ranging from place to place. Coral will vary widely in habitat from shallow 3-5ft soft coral waters to deep hard coral found over 1000m underwater. The most precious coral for jewellery is the red coral of the Mediterranean, originally found 100ft under water by early fishermen.

This precious coral was thought to be extinct until divers located caves as shallow as 10-12ft containing this red coral species.

Q. So if you’re looking for a piece of jewellery containing red coral, how do you identify it as genuine and not an imitation?

Corals are fairly easy to differentiate with most of the corals – the precious corals – having visible striations that move across the stone/bead. This identifies the growth where the small tree -like structures were with vertical striations of the stems. Many corals are treated with dye to enhance their appearance so being aware of this when purchasing coral is important as those that have been dyed are no longer considered precious. Dyed coral can be identified when a concentrated colour is found along the edges of the stone where the dye has run in a cut stone or if the coral itself is a perfectly uniform colour without imperfection.

Coral value is similar to pearl where the more intense the colour, like red, the more valuable the material is deemed to its pink and orange counterparts.

Q. Final question, I promise! Out of pearl, coral and shell, what is your favourite organic material and why?

That’s a hard one! I have a much more extensive collection of shells since I started collecting them at only 4 years old on the coast which continues till today. In this case, since I’ve been interested for over fifty years, I would probably have to say shells. I collect two main families, the Cowrie shells as well as Conch shells of which The Queen conch is one of them. It was from collecting shells that I got to love pearl, especially as I am yet to find one. The question is tricky as the pearls live inside the shells which then live beside the coral so they are all connected!

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 of Coral Skeleton and Pearl. All images courtesy of Henry Mesa, Latin American Ambassador at 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...

Speaker in the Spotlight: Q&A with Patrick Dreher

Master Carver, member of the Board of Trustees of the German Gemstone Museum and board member of the Federal Association of the Gemstone and Diamond Industry, Patrick Dreher is one of the highly anticipated speakers at the Gem-A Conference 2017 not to be missed.

Within his lecture on ‘Generations of Mastery’, Patrick Dreher will be delving into the history of Idar-Oberstein and why the town gets its reputation as a gemstone metropole. Patrick will take attendees back in history, exploring the generational legacy of the Dreher family as well as exploring how an animal carving is produced.

Gem-A caught up with Patrick Dreher to secure some exclusive insider knowledge and to find out what inspired him to pursue a career in master carving...

Q. How, when and what originally inspired you to pursue a career in carving?

I grew up in a gemstone carver family with a very long tradition working with gemstones; the history of my family goes back 13 generations. The first generation were agate cutters and the last 5 generations have been gemstone carvers. So it was more or less clear that I would follow in our family business. For me it was an easy decision to go this way, because I like nature, animals and even more so, gemstones. When I was younger I would often watch my father working, fascinated. After my first carving experience as a young child, I was sure I wanted to go on in the profession.

Q. Where do you find inspiration for your commissioned carvings?

Nature and animals themselves are the best inspiration for our art objects. Gemstones also often “tell” us what they want to be or become. It sounds a little funny; how can a stone tell you what it wants to be? Before we start one of our art objects, we look for the right gemstone and examine its features. We get to observe the stone, formulate an idea and analyse what will be the best “use” for the stone and what animal wants to come out of the stone. With expensive stones like aquamarine, we have to take care that not too much is cut from the stone. We try to keep these gemstones as big as possible in terms of their dimension and weight.

Multicolour tourmaline toad, ©Bill Larson. Photo by Robert Weldon.

Q. In your presentation at this year’s Gem-A Conference, what should we expect to hear and learn from you?

I will be presenting a lecture concerning the history of Idar-Oberstein and my family. The focus upon these subjects will be the shortest in my lecture; it will only be a brief overlook. The second half of my lecture will demonstrate to visitors how a gemstone carving is produced. I want to show them the step by step motions from start to finish whilst explaining the most important steps. The final part of my lecture will consist of a slide show showcasing a variety of finished carvings we have produced in the last year.

Q. What one word or phrase would you use to describe both yourself and the mission of your work?

“The passion” for gemstones and wildlife. The combination of beauty found within gemstones, mother earth alongside the living beauty of animals.

Strawberry starfish ©Bill Larson. Photo by Robert Weldon.
  • 'Generations of Mastery’ by Patrick Dreher will take place Sunday 5 November 2017 at 09:45 - 10:45am.
  • To purchase your tickets to the Gem-A Conference 2017 and full listings of the programme, please visit the official website here.

 

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 Patrick Dreher and Silverback Gorilla ©Dreher family. Strawberry starfish and tourmaline toad, ©Bill Larson. Photos by Robert Weldon.


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An Interview with Diamond Artist Angie Crabtree

Painter Angie Crabtree has built a reputation as one of the most sought-after diamond artists, literally recreating every sparkling facet in incredible detail. Here, she shares her passion for painting gemstones (and the occasional watch movement) with Gems&Jewellery...

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What is your background and how did you begin painting diamonds?

My background is in art. I have been painting since I was four years old. I went to an arts high school and graduated from the San Francisco Art Institute in 2009. I also attended the School of the Art Institute Chicago and the Rietveld Academie in Amsterdam. I painted my first diamond - at 1.5m tall - in 2013 for a luxury-themed gallery exhibition in San Francisco.

Having known very little about diamond at the time, I began researching and found out that diamonds come in different cuts. This is where my continuous series of diamonds began!

What is it about diamond that has held your attention for so long?

Painting diamond portraits is meditative. I love learning about each one, and I love the abstract patterns and geometry. It's hypnotising! The symmetry, rainbow accents and reflections are so alluring. Every diamond is unique and presents a new challenge.

 How do people react to your work?

When I do live painting at special events, it is a great conversation starter. A handful of companies have commissioned me to paint their special stones, and invited me to paint at their event. Having a stone painted is a great way to show people the details in an up-close and personal way.

Where do you see your paintings progressing - will you be moving into coloured gemstones?

Absolutely yes! I recently started a series of fancy coloured diamonds behind-the-scenes, which I will be releasing sometime in the next year. Eventually, I will work my way to other gemstones and I really cannot wait. Recently I started painting close-ups of very detailed and unique timepieces. They are a new challenge, so I am excited to do more.

What can you tell us about the process of painting a diamond? Do you think people presume it is easier than it appears?

There is a lot that goes into the process that people cannot see just from looking at my Instagram account. Choosing the diamond, having it photographed, drawing the diamond, building the canvas, prepping the canvas, mixing the paint, base coats, layering, glazing, and weeks of drying time between coats. Even the photography is a big step; capturing the essence of my paintings - the exact colours and details - is no easy task.

Why do you think people are so enamoured with your diamond portraits?

I think people are initially interested in my work because diamonds are luxurious, but when they see them as painted works of art they become mesmerised in a new way. At least that is what drew me into the idea of painting them.

Originally, I was interested in exploring ideas of luxury through art, but after researching diamonds and gemmology, the whole series went in a new direction: it became more about getting lost in the abstract patterns, facets, reflections and colours - similar to how I fee; when I look into a kaleidoscope.

Are there any particular pieces you are most proud of?

My favourite piece is the painting I did of my engagement ring diamond. It is of an elongated emerald-cut that I picked out from my friends at Perpetuum Jewels in San Francisco. When I was searching for the perfect diamond, I knew it would eventually become a painting, so that is why I chose this one: I wanted to have a panoramic piece to hang in our home. It is the only piece I will never sell. I recently began selling phone cases printed with the diamond because, why not?! It is the perfect proportions!

What would be your advice to amateur artists who want to give painting diamonds and gemstones a try?

My advice would be to focus on not just the symmetry of the design, but also balancing of the colours and contrast. Mix all your colours from scratch so that they are in their purest form. Quality materials are important too.

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: Angie Crabtree with a selection of her diamond paintings. All images © Angie Crabtree.

Additional Info

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