Dating from the late 19th to early 20th century, the cushion-shaped sapphire was formerly owned by a European noble family.  It was the first time it had appeared at auction, attracting interest from multiple bidders, before it eventually sold to a telephone buyer, far exceeding its pre-sale estimate of £300,000-400,000.

Emily Barber, Director of Jewellery at Bonhams UK, said: “We have a strong track record of selling Kashmir sapphires at Bonhams, with our international clients eager to add an important gem to their growing collections.   We’re delighted that this impressive stone performed so well at the sale.”

The second highest performing lot was A Diamond and Sapphire Transformable Necklace by Spanish jeweller Grassy. Dated circa 1935 and featuring a show stopping 34.59 carat Sri Lankan (no heat) sapphire, the necklace sold for £287,562 against its pre-sale estimate of £120,000-180,000.  

Emily Barber commented: “This necklace is the epitome of late Art Deco jewellery design and embodies the fashion for striking, sculptural “white” jewels in diamonds and platinum.

“To discover a necklace like this today, intact and never before seen on the open market, offered with its the original design drawings, is not only rare but illustrates the compelling stories that period jewels can tell.”

Elsewhere, one of the most admired diamond lots during the sale’s preview in London, Geneva, Hong Kong and New York was A 9.07 carat step-cut Diamond Ring. The step-cut diamond, F colour, Type IIa and VVS1 clarity (potential), sold for £250,062.

A Diamond and Sapphire Transformable Necklace by Spanish jeweller Grassy. Sold for £287,562 

Remarkable lot steeped in jewellery history attracts bidders globally

The historic legal agreement that facilitated the cutting of the world’s largest diamond and created diamonds that now form part of the Crown Jewels and the collection of Her Majesty Queen Elizabeth II also caught the interest from both media and buyers globally. 

 The original 1908 manuscript copy of the ‘Agreement for the Inspection of the Cullinan Diamond’ between the representatives of King Edward VII and London diamond brokers M.J Levy & Nephews also went under the hammer.  It was accompanied by a paste replica of the Cullinan in its original rough crystal form and two replica sets of the nine principal diamonds cut from the uncut diamond.

 This document brokered the cutting of the 3,106 carats diamond – still the largest gem-quality rough diamond ever discovered - by the renowned Asscher Company in Amsterdam to create the nine principal Cullinan Diamonds that today form part of the Crown Jewels of Great Britain and the collection of HM Queen Elizabeth II.

 Given its historical significance, there was lively bidding from buyers present at the sale as well as online and on the ‘phones before the lot finally sold for £21,312, seven times its pre-sale estimate of £2,000-3,000.

Modern British Jewels rule Britannia at Bonhams

The sale also featured an exceptional collection of jewels from the British Modernist movement, dating from the 1960s to the 1980s, created in the jewellery studios of London.  The collection included works by Andrew Grima, Charles de Temple, David Thomas and Kutchinsky.  Top performers included:

• A Diamond and Gold Necklace by Charles De Temple, 1985,  which sold for £18,812 against its pre-sale estimate of £5,000-7,000.This necklace is part of a series by Charles de Temple called ‘nervous jewels’, these were prickly sculptural constructions created from bicoloured gold wire.
• A Gold, Amethyst and Diamond Pendant Necklace, 1971, from the founder of the modernist movement, Andrew Grima, which sold for £16,312 against its pre-sale estimate of £10,000-15,000.
• A Gold, Green Tourmaline and Diamond Bracelet by David Thomas, circa 1970, which sold for £12,562 against its pre-sale estimate of £6,000-8,000. David Thomas is a much-celebrated master goldsmith and is known for his exceptionally skillful use of gold, creating highly refined individual jewels, which rarely come up for sale at auction.

 Emily Barber commented: “These pieces showcase the bold and readily identifiable style associated with the post war modernist movement in jewellery.  These jewellers are seriously in demand today and always perform well at our auctions.”

 Ring formerly owned by Andy Warhol creates buzz at Bonhams

An Emerald and Diamond 'Two Bees' ring by Jean Schlumberger for Tiffany & Co dating from the mid 20th century sold for £100,062 against its pre-sale estimate of £65,000-85,000. The ring was in the collection of Andy Warhol, who was an avid - yet secretive - collector of jewellery.  The ring features an impressive 22.02 carat step-cut Colombian emerald, sitting within an elaborate mount formed of two marquise and brilliant-cut diamond honey bees and two curving brilliant-cut diamond leaves.