If you own jewellery and you're wondering how much it might be worth, having it valued by an auctioneer is the wisest choice according to. . .well. . .Sotheby's auctioneers.
Mr Humphrey Butler, a senior director of the jewellery department at Sotheby's, says: "For impartial advice, the auction houses represent a very fair barometer [of values] because of the volume of goods they see through their hands. And equally they're trying to market the piece as best they possibly can because the more they make the more commission they take."
If the piece is by one of the top names like Cartier or Van Cleef & Arpels, it will carry a signature. Some makers just use a marker and number but most top makers use the signature in full. "The signature provides a great cachet. That is a serious selling point," Mr Butler says.
But if a piece of jewellery is not signed and you want to know what it's worth, he says: "I think, although it sounds biased, I would have to suggest that an auction house is the best way of establishing the open market value of any particular item."
Most jewellery does not carry a signature. For instance, of some 200 lots in a Sotheby's fine jewellery auction in London on October 7th, only 37 are signed.
Auction houses "will give you an estimate. It's a forked estimate, that is to say it's going to fetch between £100 and £150 or between £1,000 and £1,500 or between £5,000 and £7,000. If you were interested in selling it at that price you would then put on a reserve, which is a form of insurance, it's a protective figure.
"If the bidding doesn't actually reach that figure then the auction house will withdraw it or buy it in on your behalf. And there might be a small charge to pay for the illustration or the insurance but otherwise no other money changes hands and you get the piece back."
Speaking candidly, Mr Butler says: "It's changed so much in my time, in the 20 years that I've been in the business. The auction houses used to be a clearinghouse for impoverished, private vendors to get rid of their property, raise cash, and they would be selling almost exclusively to the trade.
"So the trade had things pretty much their own way and then what the trade were buying for £100 today would be in their shop window for £200-plus tomorrow. Nowadays, the private buyer has got much more discerning. He's got much more educated with regard to the auction process. "There's no stigma attached to being seen to buy at auction. And from buying - it's a dreaded expression in our world - but `second-hand', they actually enjoy it. They enjoy the whole process, coming to the view, the buzz, the excitement of competing."
Auction staff are well qualified to give advice as to whether the mounting is in good condition, whether the stones have cracked or are secure in their settings; whether the colour is good, the clarity is perfect or not quite so, he says. The forthcoming Sotheby's auction includes an octagonal stepcut diamond weighing 6.28 carats mounted on a ring by Cartier (estimate: £50,000 to £60,000 sterling); an oval brilliant-cut 5.39 carat diamond ring (estimate: £40,000); and a cultured pearl and diamond snowflake brooch previously in the estate of actress Ingrid Bergman, which is expected to fetch £6,000 to £8,000.
The Irish Antique Dealers' Fair takes place at the RDS, in Dublin, from Thursday, September 30th, to Saturday, October 2nd, from 12 noon to 9 p.m; and on Sunday, October 3rd, from 11 a.m. to 6 p.m.
