It was the disappearance of one piece in particular that caused consternation, however: a rare 50-carat blue diamond the size of an egg. Only about 1 in 10,000 diamonds has a distinct body colour ...

A 17.97-carat Burmese ruby ring, estimated to sell for $5.5M, will be a highlight at The Geneva Jewels Auction: Three on ...

A very rare blue diamond sold for over $40m (£32m) at a Christie's auction in Geneva, news agencies said. The 17.61 carat, pear-shaped Bleu Royal diamond, set in a ring, fetched $43.8 million ...

This is because the two elements share similar weights and properties. "The diamonds can range from clear to very deep blue," Martoia said. "The more boron, the deeper the blue." She added that it ...