From discovering rural African mines to hand-delivering clients the world’s most precious gemstones, De Beers' Andrew Coxon tells us why sourcing diamonds is an extraordinary adventure
Growing up on the British Isles, as a schoolboy I was always interested in minerology, so when my family was posted to Brazil, I was quickly drawn to the world of coloured gemstones after being introduced to my mother’s favourite jeweller. It was my job, according to my father, to stop my mother from adding to her collection, but the jeweller easily distracted me with a sack of uncut aquamarines. After sorting through the pile, she invited me to select five pieces that were then cut and polished. That was the moment I fell in love with gemstones and when I was first told that De Beers was the best diamond company in the world. Fast-forward to today and I’m the president of De Beers Institute of Diamonds.
One of the most outstanding pieces I’ve had the pleasure of working with is a 10.1-carat diamond called De Beers Millennium Jewel 4. It is the largest oval-shaped fancy vivid blue diamond to ever appear at auction, and sold for a record price of US$32 million during the Sotheby’s Hong Kong Magnificent Jewels & Jadeite sale in 2016.
The Millennium Jewel 4 was one of 11 blue diamonds that I chose to form the De Beers Millennium Jewels collection in 2000. All these diamonds were formed at the historic Cullinan Mine in South Africa, which continues to be the best source of exceptional blue diamonds in the world. This says a lot, considering blue diamonds make up less than 0.1 per cent of all diamonds recovered at the mine.
All 11 were extremely complex and the largest was kept in a cardboard box, which had been tied with a pink ribbon and sealed with red wax. It weighed 165 carats before cutting and polishing, and was incredibly deep in colour, with long flaws that criss-crossed inside of it. It was a huge challenge to cleave safely—it could have shattered so easily. I had nightmares of it exploding into a pile of blue dust.
See also: The Rise Of Coloured Gemstones And How To Wear Them