Hidden Treasures: selling jewellery at auction

Ahead of the Summer Jewels auction on 1 August, we speak to Head of the Jewellery Department Sarah Duncan about the latest trends and what to look out for when selling jewellery at auction.

The sale of a diamond ring at Sotheby's last month, which was purchased for £10 at a car boot sale and realised an extraordinary £650,000 at auction has emphasized the potential value of treasures that may be lurking in jewellery boxes.

However, diamonds are not the only pieces that are valuable. In fact, other gemstones have gained significant value in recent decades, with noticeable changes taking place in terms of the type of gemstones realising the highest value at auction. At the moment, it is organic materials and signed vintage pieces that are performing well under the hammer.

Pearls are an apt illustration of the fluctuating jewellery market. The demand for natural pearls reached a peak approximately five years ago and while they continue to command strong prices, the market has balanced out and buyers are choosing where to invest more thoughtfully.

'Look out for pearls which may look at little off round, or not completely uniform in shape. Natural pearls form in a very similar way to cultured pearls but may not have the exact uniformity of body shape so it could be a good indicator.' - Sarah Duncan

Amber and coral are other examples of a shifting market. Collectors are prepared to pay for natural, untreated amber and antique coral. Amber was incredibly popular in the early 20th century and is even more desirable today. It is also possible that pieces were handed down, with inheritors unaware of their potential value.

'With both amber and coral, colour can be a crucial factor. Certain intensities of hue can make a big difference in price. The most recent sale at Chiswick Auctions included an impressive certified amber necklace which competitive bidding saw sell for almost ten times its pre sale estimate.' - Sarah Duncan

The enigmatic question of origin can arise with Jewellery that is inherited. If a piece has been made by renowned houses such as Cartier or Tiffany & Co, it can command a significantly higher value in comparison to a similar, unsigned piece. Signatures or maker's marks are notoriously hard to decipher and it requires a trained eye to recognise something which could impact hugely on value.

'Look out for tiny marks on the back or side of the jewellery. Just because you don’t recognise the mark doesn’t mean it might not be important. Sometimes these marks take a lot of research but it can be worth the investment in time to see a great result for our vendors.' - Sarah Duncan


Here are a couple of highlights from the forthcoming auction taking place on 12 September:

mother of pearl onyx alhambra necklace van cleef & arpels

mother of pearl onyx alhambra necklace van cleef & arpels
A mother-of-pearl and onyx 'Magic Alhambra' necklace, by Van Cleef & Arpels. Estimate: £2000 - £3000.

tiger's eye and diamond pendent earrings, by J. Rossi
A pair of tiger's eye and diamond pendent earrings, by J. Rossi, circa 1975. Estimate £400 - £600.

Entries are currently invited, contact Head of Department Sarah Duncan with images for a free valuation: jewellery@chiswickauctions.co.uk.