Diamond Certificates and Serial Numbers: A Counter Guide
How jewelers record lab report numbers, link each certificate to the stock item and sale, verify reports on the lab's site and disclose lab-grown stones.
By GetJewelryPOS Editorial Desk · Published · Updated
Key takeaways
- A diamond's lab report number is its identity in your records: store it against the stock item, print it on the invoice and keep it with the customer's purchase.
- Verify every report on the issuing lab's own website (GIA's Report Check is one example) before you buy or sell the stone, not after.
- Match the stone to the report: measurements, weight, shape and any laser inscription. A genuine report for a different stone proves nothing.
- Disclose lab-grown diamonds clearly in writing, on the tag and on the invoice; in the US the FTC Jewelry Guides address how they should be described.
- One serial per piece, one report per stone, one sale per serial: that chain is what lets you answer any question about a piece years later.
Diamond certificates and serial numbers work together: the lab’s report number identifies the stone, your serial or stock number identifies the piece it is set in, and your records link both to the sale and the customer. Record the report number against the stock item, verify the report on the lab’s own website, match the stone to it, and print it on the invoice.
Done every time, this turns a stone from “the 1-carat oval in tray 2” into a piece with a traceable history: where it came from, what the lab said, who bought it, and when it came back for a prong repair. This guide covers what a report number is, how to record it, how to verify it, and how to handle lab-grown disclosure.
What is a diamond grading report number?
It is the unique number a gemological lab assigns to the report it issues for one specific stone. GIA, IGI and HRD are among the labs that issue reports, and each uses its own numbering. The number is the key for looking up the report online and, when the stone carries a laser inscription, for matching the stone to the paper.
The trade often calls these reports “certificates” or “certs”. Strictly, most labs call them reports: they describe the stone’s characteristics at the time it was examined. They do not value the stone and they do not guarantee anything about the setting it later goes into.
Report, appraisal and your own tag
| Document | Who issues it | What it says | What it does not say |
|---|---|---|---|
| Lab grading report | A gemological lab (e.g. GIA, IGI, HRD) | Weight, shape, measurements, color, clarity, cut where graded, origin type | The value, or anything about the mounting |
| Appraisal | An appraiser | An estimated value, often for insurance | A lab grading of the stone |
| Your stock tag and record | Your shop | Serial, price, location, metal, linked report number | An independent opinion |
Keep these separate in your records. A customer who asks “is this certified?” usually means “is there a lab report?”, and the honest answer names the lab and the number.
How should you record a certificate against a stock item?
Give the piece a serial or stock number of its own, then store the lab name, report number and the main grades in fields on that item. If the piece holds more than one reported stone, record each report. Keep a scan or photo of the report with the record, and file the original where you can find it by serial.
Fields worth recording for each reported stone:
- Lab name (spelled the same way every time, so you can search by it)
- Report number
- Report date
- Carat weight
- Shape and measurements
- Color, clarity and cut (where graded)
- Natural or laboratory-grown, exactly as the report states
- Laser inscription, if present, and whether you have checked it
The piece’s own serial is what goes on the tag. The report number can go on the tag too, but at minimum it must be one scan or search away from the serial. Our serialised items and certificates page shows how these fields sit on an item.
How do you verify a report on the lab’s site?
Go to the issuing lab’s own website and look the report up by number. GIA offers a service called Report Check for this; other labs generally offer their own online verification. Compare what the lab’s site shows with the report in your hand and with the stone in front of you. Never rely on a QR code or link supplied by the seller.
A simple verification routine, used on every reported stone you buy or take on memo:
- Type the lab’s address yourself, rather than following a link on the paperwork.
- Enter the report number (and the carat weight, if the lab asks).
- Compare the online result with the paper or digital report: weight, shape, measurements, grades, natural or lab-grown.
- Compare the stone: weigh it if loose, measure it, and check the laser inscription under magnification if one is listed.
- Record the check: date, who did it, and the result, against the stock item.
If anything disagrees, stop. Do not buy, sell or set the stone until it is resolved with the supplier or the lab.
Why must the stone match the report?
Because a real report for a different stone is worthless. Reports can be separated from their stones by honest error, in a mixed parcel, or deliberately. Matching weight, measurements, shape and any girdle inscription is what ties the paper to the stone. Verification checks the report exists; matching checks it belongs to this stone.
| Check | How | What a mismatch suggests |
|---|---|---|
| Report exists online | Lab’s own site | Fake or altered report |
| Weight | Calibrated scale (loose stone) | Different stone, or recut |
| Measurements | Gauge | Different stone |
| Shape and cutting style | Visual, loupe | Different stone |
| Laser inscription | Loupe or microscope | Different stone, or inscription removed |
| Natural / lab-grown | As stated on report | Disclosure problem, or swapped stone |
Mounted stones are harder: you cannot weigh them, and prongs can hide an inscription. Measure what you can, check the inscription where visible, and note on the record what you could and could not check.
How do you link the certificate to the sale?
Sell by scanning the piece’s serial, so the sale record carries the serial and, through it, the report. Print the lab name, report number and main grades on the invoice next to the item. Give the customer the original report, or a copy if you keep the original by agreement, and note which on the sale.
That one link answers most future questions:
- Insurance: the customer’s insurer asks for the report number; it is on the invoice.
- Returns: the returned stone is checked against the report number on the original sale.
- Repairs: a ring back for re-tipping is matched to its report at intake. See our repair intake checklist.
- Upgrades and trade-ins: you know exactly what you sold, and when.
Keep the customer on the sale, too. A customer record with purchase history means a call two years later (“I bought an oval solitaire from you”) takes seconds, not an afternoon.
How should you disclose lab-grown diamonds?
Clearly, in writing, everywhere the stone is described: the tag, the display card, the invoice, the online listing and what staff say at the counter. A lab-grown diamond is a real diamond grown in a laboratory, and many customers choose it deliberately. The problem is never selling it; it is ever letting a customer believe it is natural.
What the rules say, in outline
In the US, the Federal Trade Commission’s Guides for the Jewelry, Precious Metals, and Pewter Industries (the “Jewelry Guides”) cover how diamonds and lab-grown diamonds should be described. They call for a clear qualifying term for lab-grown stones, such as “laboratory-grown” or “laboratory-created”, and treat misleading descriptions as deceptive. Read the Guides themselves on the FTC’s website for the exact wording; this summary is not legal advice.
In the UAE, Pakistan and other markets, consumer protection and trade rules apply too, and they differ. Ask your trade association or a lawyer what disclosure is required where you sell.
Practical disclosure habits
- Record origin on the item exactly as the lab report states it, and never edit it by hand without a manager login.
- Print it on the tag and the invoice: “Laboratory-grown diamond, 1.02 ct, IGI report number …” (example wording).
- Keep natural and lab-grown stock in separate trays and separate locations.
- Train staff to use the same words every time and never to call a lab-grown stone simply “a diamond” without the qualifier.
What about stones without a report?
Many stones, especially melee and smaller accent stones, have no individual report, and that is normal. Describe them honestly on the item (total carat weight, approximate grades, natural or lab-grown as known from your supplier), keep the supplier’s invoice or memo reference, and do not imply a lab grading that does not exist.
For mixed pieces, record the reported center stone with its report number, and the accent stones as a group with total weight.
How does this fit with shrink control?
Serials and report numbers make a swapped stone obvious. If a customer returns a solitaire, or a piece comes back from the bench, you check the stone against the report linked to that serial before you accept it. Without that link, a lower-quality stone can come back in a familiar setting and nobody notices until the next sale. Our guide to jewelry store shrink control covers the floor routines that go with it.
How GetJewelryPOS handles certificates
In GetJewelryPOS every piece can carry its own serial or stock number, and certificate details (lab, report number, carat, color, clarity, cut) in custom fields. You can scan or search by serial, and the sale, the customer and the certificate stay linked. Each item can carry its own product warranty, and sales returns are recorded against the original sale. Print serials and prices on narrow barbell tags with jewelry tags and labels, and restrict who can edit item details with high-value inventory controls. GetJewelryPOS does not grade stones or connect to any lab; you verify reports on the lab’s own site.
What to do next
- Add lab, report number and natural/lab-grown fields to every reported item in stock.
- Verify the reports you hold on each lab’s own site and record the check.
- Separate natural and lab-grown stock into different trays and locations.
- Add the report number to your invoice layout.
- If you are moving certificate records from a spreadsheet, see switching from another POS and the plans.
About the author
GetJewelryPOS Editorial Desk · Product & trade guides
The GetJewelryPOS Editorial Desk writes practical guides for jewelry store owners in the US, the UAE and Pakistan, and tests every step in the software first.
- Articles checked against the GetJewelryPOS software before publishing
- Worked examples recalculated from the unit table in pricing.json