The green mark is copper. Sterling silver is 92,5% silver and 7,5% other metals, and the copper among them reacts with the natural acidity of skin, with sweat and with cosmetics. The result transfers onto the skin as a green stain. It sits on the surface, and soap and water removes it.
It is one of the most common worries about silver and one of the least alarming — with a single genuinely useful exception, which is at the end of this page.
What is actually happening
Copper is a reactive metal. On the surface of a chain, it interacts with moisture, with the mild acids present on skin, and with whatever else is in contact — forming copper compounds that are green or blue-green. Those compounds are soft and they rub off, which is how they end up on you rather than staying on the chain.
This is the same chemistry that turns copper roofs green over decades, running at a very small scale over a few hours.
Note that it has nothing to do with the silver itself. Pure silver does not do this. But pure silver is a good deal softer, which is why sterling exists — and the copper that makes a chain durable is the same copper that occasionally leaves a mark.
Why it happens to some people and not others
Skin chemistry varies from person to person, and the same person's skin varies day to day. The main factors:
- Sweat. More moisture and more salt means more reaction. This is why it is far more common in summer, in humid climates and after exercise.
- Cosmetics. Lotions, sunscreen and perfume sit between the metal and the skin and often accelerate things considerably. Sunscreen is a frequent culprit at the beach.
- How clean the chain is. A chain carrying a layer of tarnish and cosmetic residue has more reactive material on its surface than a freshly polished one.
- Where it sits. A bracelet against a wrist that rests on a desk, or a chain under a shirt collar, has more sustained contact and less airflow than a piece worn openly.
None of this is about the quality of the silver, and none of it is permanent.
Getting the mark off, and reducing it
The mark itself washes off with soap and water. It is on your skin rather than in it.
To make it less likely in the first place:
- Keep the chain clean. A polished chain has less on its surface to react with. This is the single most effective step: a polishing cloth every few weeks does it.
- Put jewellery on last. After lotion, sunscreen and perfume have dried, not before.
- Dry it after water. Especially after swimming or a shower — moisture left in the links keeps the reaction going.
- Take it off for heavy exercise. Or wipe it down afterwards.
If a mark still appears occasionally in hot weather, that is normal for sterling silver and not a reason to stop wearing it.
One distinction worth making: a green stain is not irritation. Reactions to jewellery are usually caused by nickel, which lives in base metals and platings rather than in sterling silver — our own alloy is 92,5% silver, with copper, zinc and indium making up the rest and no nickel anywhere in it. So if something you wear irritates your skin rather than simply marking it, the first job is working out which piece is responsible; and if it is genuine irritation, that is a question for a professional rather than a jewellery blog.
The one case where it does tell you something
Sterling silver is capped at 7,5% non-silver metal, and only part of that is copper. It is a small amount, so the effect it produces is correspondingly mild — an occasional faint mark, usually in heat, usually after hours of wear.
Green that appears quickly, darkly and every single time is a different signal. That much copper reaction points to a piece with far more copper in it than sterling permits — typically brass or another base metal under a thin silver or rhodium layer, sold as 925 regardless of what it actually is.
So the rule of thumb: a light mark after a long hot day is sterling behaving normally. A dark ring after an hour, reliably, on a piece stamped 925, is worth investigating. Weight is the fastest way to check — a plated base-metal chain will not weigh what solid sterling of the same size weighs, and the gram weight on a product page is the number that settles it.
Every Neviera chain is solid 925 sterling silver, made in Italy, with the gram weight of every size published on its product page. If you are still deciding between styles, our guide to the four silver chain styles puts Cuban, curb, Franco and rope side by side.