How to Verify a Jewellery Supplier's Lab Test Report (Accreditation, QR Check, Red Flags)
A jewellery supplier's lab test report is only worth something if three things check out: the laboratory is accredited, the report can be confirmed with that laboratory directly, and the tests on it are the ones that matter for the product you are buying. A real report carries a unique report number, the applicant's name, a description of the sample, the standard used for each test, measured results next to the legal limits, a signature and the laboratory's seal. If any of those are missing, or the laboratory cannot confirm the report number, treat it as unverified.
This guide walks through what to look for on the page, how to check a report in a few minutes, and which tests are relevant to stainless steel and plated jewellery sold in the EU, UK and US.
Who issued it: accreditation comes first
Anyone can print a PDF with the words "test report" on it. What gives a report weight is the laboratory's accreditation: an independent national body has assessed the lab's methods, equipment and staff for the specific tests it performs. In China the national accreditation body is CNAS, and an accredited laboratory shows a registration code such as "CNAS L3068" on its reports. In the UK the equivalent body is UKAS, in Germany DAkkS, in France COFRAC, and in the US A2LA among others.
These national bodies recognise each other through the International Laboratory Accreditation Cooperation (ILAC) mutual recognition arrangement. In practice this means a result from a CNAS-accredited laboratory carrying the ILAC-MRA mark is accepted on the same footing as one from an accredited lab in Europe. One detail is easy to miss: accreditation covers specific test methods. Reports often mark methods that sit outside the lab's accredited scope, so read the footnotes.
What a genuine report shows, page by page
Most third-party jewellery reports follow the same structure. Before reading any result, check that the frame around it is complete:
- Report number and page count on every page ("Page 2 of 6"). Missing pages are a reason to ask for the full document.
- Applicant and sample description: who paid for the test and what was tested (for example "gold-tone stainless steel earrings").
- Dates: when the sample was received, the testing period and the issue date.
- Standard and method for each test, the limit, the limit of quantification (LOQ) and the measured value.
- A conclusion per test (PASS/FAIL), the signature of an authorised person and the laboratory's seal.
The table below shows which tests are relevant to metal jewellery and what each one actually tells a buyer.
| Test | Standard | What it tells a buyer |
|---|---|---|
| Alloy composition | ASTM A959 element limits (by spectrometry) | Whether the steel is really 316, 304 or something else |
| Nickel release | EN 1811 (REACH Annex XVII entry 27) | How much nickel leaves the metal in contact with sweat, the figure EU law limits |
| Coating wear before nickel test | EN 12472 | For plated items: whether the coating keeps nickel release low after simulated wear |
| Lead | REACH Annex XVII entry 63 | Lead content of jewellery parts, limited to 500 mg/kg in the EU |
| Cadmium | REACH Annex XVII entry 23 | Cadmium in metal parts, limited to 100 mg/kg in the EU |
How to check a report in five minutes
- Scan the QR code or find the verification link. Most accredited labs print a QR code that opens the report on the laboratory's own system. Check the address: it should be on the laboratory's own domain, and the page should show the same report number, date and a status such as "Valid".
- If there is no QR code, contact the laboratory with the report number. A genuine lab will confirm whether the report exists.
- Match the numbers. For 316 stainless steel, chromium should be 16-18%, nickel 10-14% and molybdenum 2-3%. Molybdenum is what separates 316 from 304.
- Check the grade claim against the carbon figure. 316 allows up to 0.08% carbon, while 316L must be 0.03% or lower (see 316L stainless steel). A supplier selling "316L" with a report showing 0.06% carbon is describing 316.
- Ask what the sample represents. A report states results for the sample tested; ask which material, supplier or batch it stands for.
Red flags that usually mean trouble
- No report number, or a number the laboratory cannot find.
- A QR code that opens an image, a file-sharing link or a domain unrelated to the lab.
- A "nickel test" based on alloy content alone when the buyer's market regulates nickel release (EN 1811).
- A report described as a "certificate", or a certificate with no test data behind it.
- Fonts, logos or signatures that look pasted in, or a report missing pages.
How to verify this when buying wholesale
When comparing wholesale suppliers, ask each one for the report number and the verification route before ordering, not after. A supplier with nothing to hide will send both straight away. As a worked example, Jewena publishes its third-party report CTT26090107358EN, issued in October 2026 by CTT, a CNAS-accredited laboratory (CNAS L3068, ILAC-MRA). Its 316 stainless steel passed composition to ASTM A959 (chromium 17.83%, nickel 11.62%, molybdenum 2.29%, carbon 0.064%), EN 1811 nickel release was not detected (below 0.05 µg/cm²/week), lead measured 22 mg/kg and cadmium was not detected. Every page and the lab's QR code are on the Jewena test reports page, so the check above can be run on it directly.
FAQ
Is a test report the same as a certificate?
No. A test report records measured results for a sample under named standards. A certificate is a separate statement, usually from a certification body, and is only meaningful if test data supports it. For jewellery compliance, buyers normally ask for test reports.
Can I trust a report from a laboratory in China?
Yes, if the laboratory is accredited and the report can be verified. CNAS is a signatory of the ILAC mutual recognition arrangement, so results from a CNAS-accredited lab are recognised alongside those from accredited labs in Europe and the US.
How can I tell 316 from 316L on a report?
Look at the carbon value. Both grades have similar chromium, nickel and molybdenum; 316 allows up to 0.08% carbon and 316L requires 0.03% or less.
Does one report cover a supplier's whole range?
A report states results for the sample tested. Ask the supplier which material or line the sample represents, and request further tests on specific items when a customer or market requires them.
For the rules behind the nickel figure, see the guide to earrings for sensitive-skin ranges, or browse wholesale stainless steel jewellery with public prices.