Questions people ask before they trust us with a report number.

KimeGem is a free registry that watches for the same diamond grading report number being claimed by more than one person. You register the report number of a diamond you own or are about to buy, and if somebody else registers the same number, both sides are alerted.

Think of it as a duplicate-claim alarm for certificate identities. It is not a marketplace, and nothing you register is published anywhere.

A grading report describes one specific stone. The paper itself, and the number printed on it, can be photographed, copied into a listing, reprinted onto a fake card, or attached to a completely different stone.

Because there has never been a shared place to notice that, the same genuine number can sit behind several different sales at once and nobody involved can see the others. KimeGem makes that overlap visible.

No, and this is the most important limit to understand. We never see your stone. We cannot test it, grade it, value it, or confirm that it matches its report.

What we can tell you is that a certificate identity is being claimed more than once, which is the point at which it is worth asking the seller, the marketplace, your insurer, or the grading laboratory some hard questions.

A clear check is also only a snapshot of right now. It does not mean the number is safe forever — someone else can register the same number tomorrow. Check again just before you pay, and register the number yourself so you are told if that happens.

Registering report numbers, building your trust score, and receiving duplicate-claim alerts are all free.

Owners who want an early warning that their certificate identity has surfaced elsewhere; buyers who want to check a number before money moves; and people who inherited or were gifted a stone and want a record that they hold it.

GIA — Gemological Institute of America. A non-profit founded in 1931, widely treated as the reference standard for diamond grading, and the body that created the 4Cs and the D-to-Z colour scale.

IGI — International Gemological Institute. Founded in Antwerp in 1975, the largest laboratory by volume and the one you will most often see behind lab-grown stones and finished jewellery.

GCAL — Gem Certification & Assurance Lab, now GCAL by Sarine. Known for optical light-performance measurement and a guaranteed grading accuracy policy.

GSI — Gemological Science International. Founded in 2005, with a large presence in retail-chain and mass-market grading.

They are the three trust levels a registered entry can reach. T0 means the report number was confirmed against the grading laboratory. T1 (Medium conflict trust) adds a verified photograph of the physical grading card. T2 (High conflict trust) adds verified proof that you own the stone.

A higher tier does not make your claim more true; it makes it more evidenced. Because a bare report number can be typed in by anyone who has merely seen it — on a listing, a receipt, a screenshot — a second T0 entry on your number is counted, not treated as a conflict. It only becomes a conflict once a rival claim actually reaches T1 or T2.

They are used interchangeably in the trade, but laboratories deliberately say "report", not "certificate". A report is a description and an opinion about one stone on the day it was examined. It is not a guarantee, a title deed, or proof that whoever is holding it owns the stone.

That gap between "this report is genuine" and "this person owns the stone it describes" is exactly the gap KimeGem watches.

It is how we match your report number against everyone else’s without keeping a searchable list of numbers. Your number is run through a keyed one-way function (HMAC-SHA256) and only that output is compared. The number itself is stored encrypted with AES-GCM.

The practical effect: we can tell that two entries are the same number, but a stolen copy of the database is not a shopping list of diamonds.

Carat — weight, not size. One carat is 0.2 grams. Prices step up sharply at round weights such as 1.00ct, which is why 0.99ct stones exist and are often better value.

Colour — how little colour is present, graded D (colourless) through Z (light yellow or brown). D, E and F are colourless; G through J are near-colourless and usually indistinguishable once set.

Clarity — internal and surface characteristics, graded FL and IF (flawless, internally flawless), then VVS1–VVS2, VS1–VS2, SI1–SI2, and I1–I3. "Eye-clean" usually begins around VS2 or SI1 depending on the stone.

Cut — how well the stone was proportioned and finished, graded Excellent to Poor. It is the only C that is purely human workmanship, and it drives sparkle more than the other three combined.

A report number and date; measurements in millimetres; shape and cutting style; polish and symmetry grades; fluorescence; a plotted diagram of the stone’s inclusions; and often a laser inscription number engraved on the girdle.

The girdle inscription is the single most useful field for a buyer: it physically ties that stone to that report, and a jeweller can read it under magnification in front of you.

Chemically and optically they are the same material. The difference is origin: one formed in the earth, the other in a reactor, by CVD (chemical vapour deposition) or HPHT (high pressure, high temperature).

Reports state which is which, and lab-grown stones must be described as such. They are also far less expensive, so a stone represented as natural but graded as lab-grown is a serious discrepancy, not a technicality.

Every one of the four laboratories publishes a free report-lookup tool on its own website. Type the number in and compare every field on screen against the paper in your hand, and against the stone.

KimeGem performs this check for you when you register a number, but doing it yourself before you pay is always worth the two minutes.

A report that cannot be found on the laboratory’s own lookup tool. A photocopy or PDF instead of the original card. Measurements or weight that do not match the stone. A missing or mismatched girdle inscription. A price far below comparable stones. Pressure to complete quickly or to pay outside the platform.

And, of course, the same report number appearing behind more than one listing — which is the one KimeGem was built to catch.

Install the app, sign in with Google or Apple, and enter the laboratory and the report number. We check it against the grading authority, usually within 24 hours. Until that check clears, the entry is pending and is not matched against anyone.

Photograph the physical grading card with the in-app camera to reach T1. Add a photograph of the purchase invoice, plus up to three photographs of the jewellery, to reach T2. A reviewer checks each piece of evidence before the tier changes.

Because a file can be anything: a screenshot, a saved image from a listing, someone else’s document. Requiring a live camera capture raises the effort of passing off evidence that was never in your hands.

You get an alert at whatever tier you chose in Notify Me. The alert shows the other claim’s trust score and roughly when it appeared, and nothing else — no name, no email, no address, no exact timestamp.

From there, the next move is outside KimeGem: verify the report directly with the laboratory, check the girdle inscription against your stone, and raise it with whoever else is party to the sale — see the next question for the full checklist.

Verify the report number directly on the laboratory’s website. Check the girdle inscription on your stone. If a purchase is in progress, pause it. Tell the marketplace or dealer, and if you believe a crime has occurred, your local police and your insurer.

A conflict is a reason to slow down and check. It is not, by itself, proof that anyone has done anything wrong.

Yes. Any entry can be deleted from your vault at any time, and deleting it removes it from community matching. You can also mark the whole account for deletion in Settings; it completes after a seven-day grace period.

Verification runs against the grading laboratory’s own systems and we target 24 hours. Some laboratories rate-limit or challenge automated lookups, so a small number of entries go to a human reviewer instead, which takes longer.

No. There is no public register, no search, and no browsing. A searchable directory of who owns which diamond would be a gift to exactly the wrong people, so it does not exist. Matching happens internally and results are shown only to the parties involved.

You, and an authorised reviewer checking that specific claim. Evidence is held in a private store, served only over authenticated requests, and never cached. It is never shown to the other party in a conflict.

Your claim’s trust score and the approximate week it was registered. Not your name, email, address, phone number, photographs, or the exact time you registered.

Yes. KimeGem can only compare what it is shown, so if a photo of your card, invoice, or the stone itself ends up somewhere else — a marketplace listing, a shared drive, social media — nothing stops someone else from submitting that same image against your report number.

Camera-only capture and the trust-tier ladder raise the effort required to pass off evidence that was never in your hands, but neither can eliminate it. Keeping your own photographs private is the one precaution that is entirely in your control.

Your sign-in identity, the encrypted report numbers you registered, the evidence you chose to upload, your notification settings, and an audit trail of actions taken on your entries.

The Privacy Policy lists every category and the retention rule that goes with it, and the Terms set out what you may and may not use the registry for.