An Important And Rare Emerald And Diamond Ring, David Webb An Important jadeite and diamond 'Guanyin' Pendant

Many territories now produce exceptional gems. Graeme Thompson tells Lucinda Bredin how Bonhams masters this new landscape

"It's almost a sixth sense I use when encountering gemstones. They come in such a rich variety of colours, but sight alone doesn't explain it," says Graeme Thompson, Director of Jewellery for Bonhams Asia.

We're discussing a 10.21-carat Kashmir sapphire ring, by Mouawad, that he sold for HK$7,500,000 (US$966,349) in November last year – and he admits to engaging his sixth sense constantly at work. "There's something about the beauty of gemstones... maybe it's to do with the remarkable process by which they reach ground level and ultimately someone's finger – after millions of years and starting out hundreds of miles beneath the earth's surface."

Coloured a rich lustrous blue, sapphires from Kashmir are what you might call classic gems, their discovery dating back to the 1880s (as a result of a landslide in India's remote Kudi Valley). In Bonhams' forthcoming Rare Jewels and Jadeite sale in Hong Kong on 31 May, however, Thompson will be broadening horizons, bringing to auction pieces from lesser-known parts of the globe.

"Many important new gem deposits have been discovered in recent years," he says, "and this could transform the jewellery market. The gemstones from these 'newer' regions are of excellent quality – comparable to those from traditional regions – but relatively undervalued. It's a really exciting time."

Thompson cites sapphires from Madagascar, rubies from Kenya and Mozambique, and emeralds from Brazil as examples of new or non-traditional sources – all of which will be represented at Jewels of the World. "Madagascar sapphires are so similar in chemical composition to Kashmir sapphires that they're practically identical stones – owing to the fact that, once upon a time, both areas were landlocked. Yet, the former are valued at about a tenth of the price of the latter – which makes this a great time to buy."

Born to Scottish parents living in South Africa, Thompson moved to the UK aged 10 and attended Loretto, outside Edinburgh, the oldest boarding school in Scotland. His first job was as a stockbroker for Laing & Cruickshank, before he tumbled into the world of jewellery pretty much by accident. "In 2002 I'd just returned from a year travelling and was desperate for money. One day, at an art exhibition in Edinburgh, I bumped into a gentleman called Joseph Bonnar – who was a specialist in antique and period jewellery. He offered me a job. I can only assume it was because he thought I'd make a good salesman, as I had zero knowledge of jewellery at the time. My initial reaction was 'No way, jewellery's for girls', but I was so short of cash, I had no choice but to accept. And thank goodness I did. Joseph has a wonderful, Aladdin's cave of a shop in the heart of Edinburgh, and I learned so much from him about stones, periods, and techniques.

"There were funny moments though. Once when I was giving the shop windows the morning wash, an Irn-Bru delivery truck pulled up. While the stock was being unloaded into the pub on the corner, the driver turned to his colleague and said in a broad Glaswegian accent 'I telt you Edinburgh was posh – even the window cleaners wear a suit'!"

Captivated by the jewellery world, Thompson subsequently completed a degree in gemmology at the Gemmological Institute of America in New York. In 2006 he became Bonhams Jewellery Specialist in London, before starting his current role, in Hong Kong, in 2013.

So far, the standout moment has been his sale of an extremely rare collection of flawless, hearts-and-arrows diamonds for HK$20,280,000 (US$2,616,774) in 2014. How about some of the challenges? "There's certainly the fear, as auctioneer, of pronouncing a name wrong."

The market in Hong Kong is also very different from America or Europe. As Thompson points out, "Jadeite, a stone unique to China, pretty much runs in the blood here. For the Chinese, it represents good health and long life. A jewellery specialist here is nowhere without a proper appreciation of jadeite."

Thompson says his main clients are, like his office, in Hong Kong, but he is looking to extend the market into Taiwan, Singapore and mainland China. To that end, he holds widely acclaimed masterclasses in those places to give potential buyers a thorough grounding in jewellery, so they can confidently tell an Art Deco piece from a 19th-century one.

One buyer who benefited from Graeme's tutelage was his brother-in-law. "I actually sold him the engagement ring with which he proposed to his fiancée. It was the first time he'd ever attended an auction. One of the many things Bonhams prides itself on is the way in which we look after people who are new to the saleroom. But in the case of my brother-in-law, no matter how many people were there to mop his brow, he was incredibly nervous. During the bidding, he just kept his hand in the air throughout, without really even looking at me. Afterwards I went over to him and asked how he felt, to which he replied, 'I've no recollection of what happened whatsoever – but I know I got the ring because they've already taken payment.'"

Lucinda Bredin is Editor of Bonhams Magazine.

Sale: Rare Jewels and Jadeite,
Hong Kong,
Wednesday 31 May at 3pm.
Enquiries: Graeme Thompson +852 3607 0006

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