To test nickel in jewellery, a spot test kit can tell you whether nickel is present at the surface, but only a laboratory test shows whether the nickel release is within the legal limit. To test lead in jewellery, a spot kit can screen the surface, while a laboratory measures the lead content of the whole article. Use kits to screen, and use labs for anything you must prove.
Compliance with the EU, UK and US rules rests on lab reports, not on kit results.
What can a spot test kit tell you?
A nickel spot test usually uses dimethylglyoxime. You rub a swab on the metal, and a pink or red colour suggests nickel is available at the surface. A lead spot test uses a reagent that changes colour in the presence of lead.
These kits are quick and cheap, and they help in a factory or at a goods-in check. They also have limits. They test the surface, so a plated top coat can hide a leaded or nickel-bearing base. They give a yes or no, not a measured release or content. And a negative result is not proof of compliance.
What does a laboratory test measure?
Labs measure the quantities the law sets limits on. For nickel, the EN 1811 method measures release into artificial sweat, and the EU limits are set per square centimetre per week for articles in prolonged contact with skin and for piercing posts. Details are in the EN 1811 nickel release test.
For lead, a lab digests a sample and measures the metal content with instruments such as ICP or AAS. The EU limit for lead in jewellery under REACH is 0.05% by weight, as covered in the EU lead limit under REACH. US children's jewellery has its own limits, covered in CPSIA lead limits.
XRF is a third approach. It is fast and non-destructive and good for screening a batch, but it does not measure nickel release. See XRF testing explained.
Which should you use and when?
Use each tool for what it does best:
Do not skip the test because a kit was clear. The usual failure is a finished piece with a plated coating that passes a surface kit but releases nickel after sweat exposure, or a component such as a clasp or pin made from a different alloy to the body. Test every distinct material in the piece, and test again whenever the supplier changes a component or plating line.
- Spot kits for quick screening of incoming components, findings and finished samples.
- XRF for screening many pieces for lead, cadmium and other elements.
- Laboratory tests on final, plated samples for the market you are selling into, because the finish changes the result.
- A repeat laboratory test on production samples, to make sure the bulk matches the tested sample.
Next step
Choose an accredited lab, send finished plated samples, and name the destination so the correct standard is used. Then compare production against the report. See how many samples a jewellery test needs and whether the production lot matches the tested sample.
We can arrange the sampling and testing for you. Book a free sourcing review.