GemsVerified
GV Research

Gemstone auctions: where coloured stones are sold

Coloured stones reach auction through a small number of international houses and a wider set of regional ones. This page sets out how such a sale works, what a published result does and does not tell you, and which houses this ledger records.

How a sale works

Reading an auction result

Six terms account for nearly every disagreement about what a stone sold for. They are worth settling before comparing any two figures.

Estimate
The range the house publishes before the sale. It is the house’s expectation, agreed with the seller. It is not an appraisal and it is not a promise.
Reserve
The confidential minimum the seller will accept. It sits at or below the low estimate and is never published, which is why an unsold lot is not evidence of a specific number.
Hammer price
What the bidding reached when the lot was knocked down. This is the figure the trade usually quotes to one another.
Buyer’s premium
A percentage the house adds on top of the hammer, paid by the buyer. It varies by house and by band, and it is why two honest reports of the same lot can differ by a quarter.
Realised price
Hammer plus premium: the figure the house publishes after the sale. Most headline numbers you will read are this one, whether or not they say so.
Bought in
A lot that did not reach its reserve. Houses report it as unsold or pass over it. It is kept in this ledger, because a lot that did not sell tells you where the market stopped.
The houses

Houses recorded in this ledger

Listed alphabetically. GemsVerified does not rank, score or compare auction houses, and no house pays for inclusion or placement. Counts show what this ledger has recorded, not a house’s full activity.

Auction houses recorded in the GemsVerified auction ledger, listed alphabetically.
HouseSales recordedLots recorded
Bonhamsbonhams.comLondon, United Kingdom89
Christie'schristies.comLondon, United Kingdom510
Gemfieldsgemfields.comLondon, United Kingdom60
Heritage Auctionsha.comDallas, United States00
Phillipsphillips.comNew York, United States12
Sotheby'ssothebys.comNew York, United States1225

Sales recorded

The digest

New results, as they are recorded

One list, sent when results are added to the ledger. Each entry carries the house record it was read from and the date it was read.

Say whether you buy, deal, or run a house when you sign up. A dealer wants the per-carat movement, a buyer wants what the notable stones did, and the same results are written up for both.

The ledger is free to read in full and stays that way. Nothing is held back for subscribers, and signing up unlocks nothing, because nothing is locked.

One address, one purpose. Read the privacy notice for retention and rights. Privacy

Questions, answered

Gemstone auctions, answered

Can anyone bid at a gemstone auction?

Usually yes, after registering with the house and passing its identity and credit checks. Registration closes before the sale, and some sales or lots carry further conditions. The house’s own terms govern, and nothing on this page is an invitation to bid.

What does a gemstone actually cost at auction?

The hammer price is not the cost. A buyer pays hammer plus the buyer’s premium, plus any applicable tax, shipping, insurance and import duty. Budget from the realised price, not from the estimate.

Are stones sold at auction certified?

Important coloured stones are usually offered with a report from a recognised laboratory, and the catalogue states which. A report describes a stone; it is not a guarantee of value. Read what the report covers, and who issued it, before relying on it.

Why did a lot not sell?

Because bidding did not reach the seller’s confidential reserve. The reserve is never published, so an unsold lot tells you the market stopped somewhere below the low estimate, and nothing more precise than that.

Does GemsVerified sell at auction?

Not today. We intend to operate GV Auctions, a federated layer in which verified dealers and approved houses run their own catalogues. We have no commercial relationship with the houses recorded on this page and take nothing for listing them.