How do you check a diamond report number?
Type the report number into the laboratory's own lookup: IGI's report verification on igi.org, or GIA's Report Check on gia.edu. The online report must match the listing: shape, carat weight to two decimals, colour, clarity, measurements in millimetres, and "laboratory-grown" if the listing says lab-grown. Many reported diamonds also carry the number laser-inscribed on the girdle, which a jeweller can read under magnification to tie the paper to the stone.
Where to look it up
Use the laboratory's own website, not a link or QR code supplied by the seller: IGI (International Gemological Institute) at igi.org, and GIA (Gemological Institute of America) at gia.edu. Type the number yourself.
What has to match
Shape and cutting style, carat weight, colour grade, clarity grade, measurements, and whether the stone is described as laboratory-grown. The measurements are the useful cross-check: two stones can share a weight and grade, but not the exact millimetre dimensions.
Tying the report to the stone
The report proves a stone exists; the inscription proves this is that stone. Ask an appraiser or jeweller to read the girdle inscription under magnification and compare it with the report number. A report number that does not exist online, or belongs to a different weight or shape, is a reason to return the item.
Frequently Asked Questions
Is a GRA certificate the same as an IGI or GIA report?
No. The GRA cards that come with most moissanite are seller-facing certificates, not reports from an independent laboratory. See our page on GRA certificates.
Can a report be faked?
A printed report can be copied, which is why you check the number on the laboratory's own site and match the measurements and inscription, rather than trusting the paper in the box.
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