Gemstone Due Diligence: Provenance, Paperwork, Escrow

A fine stone rarely fails on its own. What fails is the paper around it, the person selling it, or the order in which money and stone change hands. Due diligence on a coloured gemstone is not a mystery reserved for laboratories; it is a short list of checks, done in sequence, that most buyers skip because the stone is beautiful and the seller is charming. Here is the sequence I run for clients before a significant purchase, and the reason for each step.

First, does the paper describe this stone

Reports and stones separate. A report travels with a parcel, gets photocopied, gets married to a different stone of similar weight, and nobody notices because nobody checks. So check. The weight on the report to the hundredth of a carat against a scale you trust. The measurements in millimetres, all three. The photograph, under a loupe if necessary, because two stones of the same weight rarely share an outline. Then the report number, verified on the laboratory’s own site. Gübelin, SSEF and GIA all offer this. A report that cannot be verified is stationery.

Second, the treatment line

This is the line that moves the money and the one most often skimmed. For ruby and sapphire the words to want are no indications of heating. For emerald the line grades clarity enhancement, and the step from none to minor is a price step. The absence of a treatment statement is not a statement of absence. I have set out how to read the whole report in order; if you read only one line, read this one, and read it on a report dated within the last few years, because criteria change.

Third, a second opinion where origin carries the price

Origin is an opinion. A laboratory forms it by comparing inclusions and trace chemistry against reference stones, and the overlaps are real. On a Burmese ruby or a Kashmir sapphire, origin can be half the price, and the sensible buyer does not let one house carry that weight alone. A second report from a second Swiss house costs a fraction of the premium it protects. Two houses agreeing is comfort. Two houses disagreeing is a negotiation you want to have before the money moves, not a discovery you make at resale.

Fourth, the chain of custody

Ask where the stone has been. A serious seller can show the invoice they bought it on, the export paperwork it left its country of origin with, and the laboratory submission in their own name. A story about an old family and a parcel from before the war is not a chain of custody. For Burmese material in particular, the route out of the country has to be proper and provable, because some markets restrict it and a stone that cannot explain itself is a stone you may not be able to sell. Provenance is the one part of a stone that cannot be recut, and it is either there or it is not.

Fifth, the seller

The stone can be right and the deal still wrong. Look at the seller the way you would look at any counterparty for a six-figure transaction: a fixed address, a history in the trade, references you can call, a willingness to put the terms in writing, and above all a willingness to let the stone go to a laboratory of your choosing before you pay. A seller who resists that last point has told you what he thinks the laboratory will say. Some of the best stones I have bought came from people I had known for years; the discipline was the same on the first day.

Sixth, the sequence of money

Never pay in full for a stone that has not been examined in your name. The clean sequence is: written terms, stone to the laboratory, report matches the description, funds release. Escrow makes that sequence enforceable. A neutral party holds the money, the stone goes to the laboratory, and the outcome of the report decides whether the money goes forward or the stone goes back. It removes the two worst outcomes in the trade: paying for a stone that fails, and shipping a stone to a buyer who never pays. Sellers who deal at this level accept it as a matter of course. Sellers who refuse it are telling you something.

Seventh, the stone in transit

Insure it, in transit and on arrival, for its replacement value on the report, with an insurer who understands loose stones. Use a carrier that specialises in them. Never let a stone travel uninsured because the distance seems short; the short distances are where stones vanish. And keep every document of the journey in the file, because the next buyer will ask.

What all this costs

A second report, an escrow fee, a specialist courier and a few days of patience. Against a stone priced in the hundreds of thousands it rounds to nothing, and against the alternative it is the cheapest insurance in the trade. The buyers who lose money on coloured stones rarely lose it to geology. They lose it to a photocopy, a story, and a wire transfer sent a week too early.

Buy the stone, then read the paper, then pay. The order is the whole method.

Questions collectors ask

Should I get a second laboratory report before buying an expensive gemstone?

When origin or a colour appellation is carrying a large share of the price, yes. Origin is an opinion formed against reference material and laboratories disagree. Two Swiss houses agreeing is worth the fee many times over; two houses disagreeing is information you want before paying, not after.

What is escrow in a gemstone purchase?

A neutral party holds the money while the stone is examined by a laboratory of your choosing. Funds release when the report matches the seller's description, or the stone returns and the money does. It removes the two worst outcomes: paying for a stone that fails the laboratory, and shipping a stone to a buyer who never pays.

Can a gemstone laboratory report be faked?

Yes, and they are. Gübelin, SSEF and GIA all let you verify a report number online against their records; do it every time, and check that the weight, measurements and photograph describe the stone in your hand. A report that cannot be verified is a piece of paper.