Verify the report first, free
Every laboratory here runs a public lookup. Enter the number, compare every grade against the printed document. A number that does not resolve, or grades that differ, ends the transaction — and it costs nothing.
Lovenhall Diamond
Verify a diamond certificate, or authenticate signed jewellery
Two questions, two answers: whether a grading report is genuine and describes your stone, and whether a signed piece is the house it claims to be.
11 laboratories and houses5 modelsFree · no account
"Authenticate my diamond" turns out to be two questions. The first is documentary: is this grading report real, and does it describe the stone in front of me? The second is about the piece: is this Tiffany ring actually Tiffany, is this Alhambra actually Van Cleef?
The first is the easier of the two, and almost nobody does it. Every major laboratory runs a free public verification service — enter the report number, compare the grades. That defeats forged and altered reports in thirty seconds. What it does not defeat is a genuine report presented with a different stone, which is why the second step is always matching the girdle inscription and the measurements to the diamond.
The signed houses are the other axis, and they are read the way jewellery is always read: hallmark execution, setting geometry, finishing where nobody is expected to look. Several of these houses will inspect their own pieces, which is a real service and is under-used.
How the reading goes
Four movements, in this order
The order matters more than the list. Two checks settle most cases, and they are almost never the ones people reach for first.
Then tie the report to the stone
Verification proves the report exists. Matching the girdle inscription and the millimetre measurements proves it belongs to this diamond. Report swapping is the commoner fraud and only this step catches it.
Read the origin field
Modern reports state whether a diamond is natural or laboratory-grown, and grown stones are commonly inscribed as such. Grown stones cost a small fraction of mined ones, so this single field is often the most expensive line on the document.
For signed pieces, look inside
Hallmark strikes, prong geometry and the finish on interior surfaces are where counterfeit jewellery economises. A metal test costs a few dollars at any jeweller and settles the hallmark question outright.
The case
Every laboratory or house the room reads
One page each, in the laboratory or house's own terms — its code system, its weighted checks, its models and what they do on the secondary market.
The free tools of the room
The other rooms
Questions we are asked
- How do I check if a diamond certificate is real?
- Enter the report number on the issuing laboratory's own free verification service and compare every grade against the printed document. Then have a jeweller match the girdle inscription and the millimetre measurements to the stone — that second step is what catches a genuine report presented with a different diamond.
- Can a diamond certificate be faked?
- The document can be forged or altered, and online verification defeats both in seconds. The harder fraud is report swapping, where a genuine unaltered report is presented with a different stone, and only the inscription and measurements catch it.
- Are grades from different laboratories comparable?
- Not directly. Each laboratory is calibrated on its own terms, and stones graded by softer laboratories commonly trade at a discount at identical stated grades. That is a pricing question rather than an authenticity one.
- How do I know if a diamond is lab-grown?
- Read the origin field on the report — modern reports state it explicitly — and have the girdle inscription checked, since grown stones are commonly inscribed as laboratory-grown. Grown and mined diamonds are optically identical, so no visual check will tell you.
- Does The Lovenhall Registry issue certificates?
- No. The house makes instruments and publishes the checks; it grades nothing and certifies nothing. For a grading report, use one of the laboratories below directly.
Lovenhall DiamondRead the stone itself
The checks tell you how it was made. The instrument tells you what it appears to be, and roughly what its kind fetches.
Open the Diamond IdentifierFree on iPhone & iPad. An estimate, never an appraisal.
Or write to the house