Why silver turns your skin green, and what the mark is telling you

A green band under a ring is one of the few jewellery problems that looks like a fault and is not. Silver does not turn skin green. Copper does, and almost every piece of silver jewellery you can afford contains copper by design. The mark is a copper salt, it sits on the surface of the skin rather than in it, and it washes off with soap. What it tells you about the piece is more interesting than the stain itself, because the speed at which it appears is a fair guide to what the metal actually is.

It is the copper, and the copper is there on purpose

Sterling silver is 92.5 per cent silver and 7.5 per cent something else, nearly always copper. Pure silver is too soft to hold a stone or a clasp, so the copper is what makes the alloy stiff enough to be worn. It is not an adulterant and it is not a corner cut.

Copper reacts with acids. Sweat contains lactic acid and fatty acids, and skin is mildly acidic to begin with. The reaction produces copper salts, mostly copper chloride and copper carbonate, and those compounds are green. They form in a thin film on the metal and then transfer onto skin wherever the two stay pressed together.

Plated jewellery does the same thing faster and for a different reason. A plated piece is brass or a copper alloy with a skin of silver on top, and brass is roughly two thirds copper. Once the plating wears through at a ring shoulder or the back of a clasp, you are in direct contact with the base metal and the green arrives in days rather than months.

Why it happens to you and not to the person next to you

Sweat chemistry varies a lot between people and within the same person across a week. The pH, the salt concentration and how much you sweat at all are the three variables, and none of them is under your control in any useful way. Somebody who never stains a ring is not wearing better silver.

Heat and humidity make it worse, which is why people notice it in summer and on holiday and conclude that something has changed about the ring. Swimming pools are the single worst environment: chlorine attacks copper directly, and it will do more damage to a piece in an afternoon than a year of ordinary wear.

Hand cream, sunscreen, perfume and alcohol gel all speed it up. Hand sanitiser is the modern culprit nobody expects. It strips the thin oxide film off the metal and leaves the fresh surface sitting against damp skin, which is the exact condition the reaction wants.

Green, grey and black are three different marks

Green is copper. It appears under rings, under the back of a pendant and along the line of a chain at the nape, and it comes off with soap and water or a little rubbing.

A grey or black smudge is different. That is silver sulfide, the same compound as tarnish, rubbed off the metal and onto your skin by friction. It is more common on a piece that has started to tarnish and is then worn against fabric or skin, and it is harmless in exactly the same way.

A yellow or pink line showing at an edge is not a skin reaction at all. That is base metal appearing through worn plating, and it is the one of the three that cannot be fixed. Look for it at the inside of a band and the back of a bale, under a phone camera at full zoom, because plating always fails at an edge first.

Staining is not an allergy, and the difference matters

A stain is a deposit on the skin. It does not itch, it does not raise the skin, and it fades when you wash. If the only symptom is a colour, nothing is wrong with you.

An allergic contact dermatitis looks completely different: redness, itching, small bumps or weeping, usually appearing after hours rather than minutes, and spreading slightly beyond the metal's footprint. Nickel is the usual cause, and a piece that stains green is not necessarily a piece that contains nickel. The two issues are unrelated and are solved by different metals.

If you react rather than stain, the material question becomes the whole question, and we have written separately about earring posts and nickel. If you stain rather than react, read on, because most of it is manageable.

What actually reduces it

Keep the piece dry and keep the skin under it dry. Take rings off to wash up, to shower and to exercise, and put hand cream on first and let it absorb properly before you put the ring back on. That one habit does more than anything else on this list.

Clean the inside of the piece, not just the outside. The film of copper salts stays on the metal and goes on working the next time you put it on, so a wipe with a soft cloth where the metal meets skin is worth more than a polish of the parts people can see. For a piece worn every day, a ring you keep on accumulates it faster than a pendant does, simply because fingers are wet more often.

Clear nail varnish on the inside of a band is the trick everybody suggests. It works for about two to four weeks and then it chips, and once it chips it holds moisture against the metal in the gap. If you use it, clean and dry the band first, keep it off the outside, and accept that you are re-doing it monthly.

If the problem is persistent, change metal rather than habits. Stainless steel contains no copper worth mentioning and will not do this. Nor will titanium. Neither takes fine detail or oxidised shadow the way silver does, which is the trade, and it is a real one: a piece like a web with recessed shadow in it reads the way it does because silver can be darkened and steel cannot.

What the speed of the stain tells you about the piece

A piece that greens your finger within a day or two, in ordinary weather, is very likely plated base metal rather than sterling. Solid sterling has only 7.5 per cent copper to work with and usually takes weeks of regular wear to leave a visible mark.

A piece that never greens anybody, never tarnishes and never changes at all is also telling you something. It is either steel, rhodium plated, lacquered, or not silver. None of those is a fault, but if it was sold to you as silver and it behaves like nothing, the description deserves a second look.

We do not publish a material on a product page unless the supplier's own documentation gives us the figure, which means some of our pages are vaguer than we would like and none of them are guesses. If you want to know what a specific piece is before you buy it, email us and we will go and read the spec for that piece. That applies to the chain as much as the pendant, because on a pendant on a long drop the chain and the charm are often made in different places.

Questions people actually ask

Why does my silver ring turn my finger green?

The copper in the alloy is reacting with acids in sweat to form copper salts, which are green and transfer onto skin. Sterling silver is 7.5 per cent copper by design. Heat, humidity, chlorine, hand cream and hand sanitiser all speed the reaction up.

Does silver turning your skin green mean it is fake?

Not by itself, because genuine sterling contains copper and will do it eventually. Speed is the clue: a mark that appears within a day or two of normal wear points to plated base metal, since brass is roughly two thirds copper and reacts much faster.

Is a green mark from jewellery harmful?

No. It is a surface deposit of copper salts that washes off with soap and water. A stain that itches, raises the skin or spreads past the edge of the metal is a different thing, usually a nickel reaction, and it needs the piece taken off rather than cleaned.

How do you stop jewellery staining your skin?

Keep the metal and the skin under it dry, take rings off before washing up and exercising, and let hand cream absorb before putting them back on. Wipe the inner surface clean rather than only polishing the front. Clear varnish on a band works for a few weeks at a time.