Jewellery turns skin green because copper in the metal reacts with sweat, moisture and skin products and forms green copper salts that rub off onto the skin. It happens when the plating is thin, worn or porous and the copper-rich base metal underneath is exposed. It is a cosmetic reaction and is different from an allergy.
You can reduce it through the base metal, the plating and the finish you specify. No imitation jewellery is immune, but the choices below change how likely it is.
What causes green skin from jewellery?
Brass is copper and zinc. Many imitation pieces use brass or copper alloys under a thin gold or silver plating. When the plating wears, or when sweat and body lotion get through tiny pores in it, copper at the surface oxidises. The product is a greenish compound that stains the skin where it touches.
Acidic sweat, humid climates, soaps, lotions and perfumes speed it up. Rings, bracelets and anything worn against skin for long periods show it first.
It is worth knowing that the stain is not a sign that the piece is toxic. A green mark is mostly copper salts and washes off. A red, itchy or blistering rash is a different problem and usually points to an allergy, most often to nickel, which is why nickel testing matters.
How can the specification reduce it?
You can lower the risk at the source. Here are the choices that make a difference:
- Specify a thicker plating on pieces worn against skin. See gold plating thickness in microns.
- Ask for a barrier layer under the final plating, as long as it meets the nickel rules for your market.
- Use a base metal that does not carry copper to the surface, such as stainless steel. See stainless steel jewellery from Rajkot.
- Choose rhodium or a hard coating over a suitable base for pieces that touch skin a lot. See rhodium plating explained.
- Add a protective lacquer or e-coat to slow tarnish, remembering that it wears off. See e-coating and lacquer on jewellery.
Is it a defect, and what do you tell customers?
Light green marks after long wear on a thinly plated piece are usually a normal consequence of the build, not a manufacturing fault. Rapid greening in the first few wears may point to plating that is too thin or poorly adhered. Test it with a sweat test on samples before you order.
Be honest on the product page. Tell customers what the piece is made of, how to care for it and what to avoid. How to care for plated jewellery has wording you can adapt.
To understand why plating fails in general, read why jewellery plating fades or turns black and base metals in imitation jewellery.
If you see green marks on returns, collect the pieces and compare them with the approved sample. If the sample was thicker or better coated, the bulk does not match and you have a quality claim. If the pieces match the sample, the specification needs to change for the next order, because the factory built what you approved.
Next step
Put the base metal, plating thickness, coating and test method into your specification, and test production samples against it. If you want a supplier shortlist that can meet that specification, book a free sourcing review.