Two Blue Diamonds, One Pendant: The £2.68 Million Bonhams Result
A pear-shaped Type IIb blue diamond with a smaller blue stone above it: a small jewel that made a large figure in 2017.
On 20 September 2017, a pendant set with two natural blue diamonds, of 4.03 ct and 0.63 ct, sold at Bonhams, New Bond Street, London, for £2,685,000 including buyer's premium. GIA graded the larger stone Fancy Intense Blue and classified it as Type IIb.
The result
On 20 September 2017, at its Fine Jewellery sale in New Bond Street, London, Bonhams sold lot 188, a two-stone pendant set with natural blue diamonds, for £2,685,000 including buyer's premium.
What it was
The main stone is a pear-shaped diamond of 4.03 ct, graded by GIA as Fancy Intense Blue, natural colour, SI1 clarity, with a separate GIA letter classifying it as Type IIb. Above it sits a square mixed-cut diamond of 0.63 ct, graded Fancy Blue, natural colour, VS1. The jewel measures 3.0 cm long, according to Bonhams.
Why Type IIb matters
Type IIb diamonds contain traces of boron, which is what gives them their blue colour. They make up a tiny fraction of all diamonds mined, so a stone confirmed as Type IIb by a recognised laboratory draws attention from collectors whenever one appears at auction.
Why a matched pair helps
Finding two natural blue diamonds of a similar tone is harder than finding one. A simple two-stone design keeps the focus on the colour of the stones rather than on the mount, which is what buyers at this level are paying for.
The lesson for owners
Whatever the size of the stone, the same principles apply to coloured gems. A report from a recognised laboratory, confirming natural colour and any treatment, removes doubt for a buyer. Keep reports, receipts and original boxes together with the jewel: they can matter as much as the piece itself when it comes to selling.
For a free, no-obligation valuation of a piece you own, send us photographs through our valuation form.
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About Mozeris Fine Antiques
Mozeris Fine Antiques is a dealer in fine jewellery, watches and silver, with offices in Mayfair, London, and Braintree, Essex. We buy and sell, and offer free valuations. Visits are by appointment.
Price as published by Bonhams, including buyer's premium. Mozeris Fine Antiques is not connected with Bonhams. No auction-house images are used; the photograph shows a piece from our own stock.
