Certification

What a report settles, and what it doesn’t

A good report settles the species beyond argument, and states the treatment to the limit of what instruments can detect. Those are the two things it is genuinely authoritative on, and they are the two that matter most.

Origin is different.A laboratory determines origin by comparing a stone’s inclusions and trace-element chemistry against reference collections, and reputable laboratories are explicit that this is an opinion rather than a measurement. Two good laboratories can disagree about the same stone. So an origin call from SSEF or Gübelin is the best evidence obtainable — and still an opinion, which is why our listings mark origin as either “stated on report” or “our assessment” rather than presenting both the same way.

Colour names are the least settled of all. Padparadscha, royal blue, cornflower and pigeon’s blood are proprietary to the laboratories that use them, and the same stone is routinely called padparadscha by one laboratory and fancy sapphire by another. A colour name on a report tells you which laboratory’s criteria the stone met, and nothing more universal than that.

Which laboratories we use

GIA — Gemological Institute of America

The volume standard. Conservative, consistent, and the report most widely recognised by insurers and at auction. Calls origin on coloured stones and identifies treatment, but does not use the trade colour names.

SSEF — Swiss Gemmological Institute

Switzerland. Among the two most respected origin laboratories in the world, and the reference for a serious sapphire or ruby. Uses padparadscha and royal blue against its own published criteria.

Gübelin — Gübelin Gem Lab

Switzerland. The other of the two. Its inclusion research is the basis of much of what the trade knows about origin determination.

GRS — GemResearch Swisslab

Widely used in the Asian trade and the origin of several trade colour terms, including its own subdivisions of padparadscha. Reads colour more liberally than SSEF or Gübelin, which is worth knowing when comparing two reports.

AGL — American Gemological Laboratories

New York. Known for its treatment analysis and for grading colour on a published, repeatable scale rather than by name alone.

Lotus — Lotus Gemology

Bangkok. Small, highly regarded on corundum and spinel specifically, and unusually candid in print about the limits of what a laboratory can actually determine.

Why we don’t use local laboratories

Certificates issued in the producing countries are cheap, quick and not consistently reliable — which is worse than having none, because a weak report looks like evidence while carrying none. We would rather tell you plainly what we know about a stone and offer you a report from a laboratory whose word actually settles the question.

Adding a report to any stone

Every stone we sell without a report can be sent for one before it ships. Tick the option on the listing and it is added to the order. The stone and the report are paid for together, the stone then goes to the laboratory, and nothing is dispatched until the report is back — so you are never waiting on a stone we are holding against a fee, and we are never carrying the cost of a report on a sale that evaporates.

When a report is essential

• Any untreated stone you intend to resell or insure. We state heat status from first-hand knowledge of stock we bought at source, and set out how we know it on every listing — see how we describe stones. But a report is what travels with the stone afterwards, and the next buyer or an insurer will want it.
• Taaffeite.It looks like a pale mauve spinel and is routinely mistaken for one — the species was originally recognised only because someone noticed a cut “spinel” was doubly refractive. Taaffeite is not listed here without a laboratory report naming the tests it ran.
• Alexandrite. Price turns almost entirely on the completeness of the colour change, and synthetic alexandrite and colour-change sapphire are both sold as alexandrite by the careless and the dishonest.
• Anything above four figures. Not because we doubt it, but because you should not have to take our word at that level, and because your insurer will want it.

Uncertified stones

Plenty of good material is sold uncertified — a report can cost several hundred dollars and take weeks, which makes no sense on a stone worth a few hundred. Where a stone has no report we say so plainly and price it as uncertified material. We do not present an uncertified stone as though it were certified, and we do not describe our own opinion in language borrowed from a report.

Choosing the laboratory

The listed price covers a report from any of the laboratories above. If you want a specific one, say so and we will confirm the fee and the turnaround before committing — typically three to six weeks depending on the laboratory and the queue.

If the report comes back materially different from how the stone was described here, the sale is off and you owe nothing — we pay for the report and keep the stone. That is the only fair way to offer it: the party making the claim should carry the cost of being wrong.

Ask about certification