Does stainless steel jewelry tarnish?
No, not the way silver and copper do. Stainless steel carries at least 10.5% chromium, which forms a thin chromium oxide film that reforms itself when scratched. It contains no copper, so it does not leave a green mark either.
By SIAFRA
No. Tarnish is a chemical reaction on the surface of a metal, and stainless steel is built to prevent one: at least 10.5% chromium forms a microscopically thin oxide film that reforms itself on contact with air. Silver tarnishes black, copper and brass go green, steel does neither.
The metallurgy is unglamorous and worth knowing, because it is the reason this material ended up in jewelry at all. Stainless steel resists corrosion by “spontaneously forming a microscopically thin inert surface film of chromium oxide by reaction with the oxygen in the air”, a layer that “can self-heal when exposed to oxygen”. (Stainless steel, Wikipedia)
Tarnish, green marks and rust are three different things
| Metal | Tarnishes? | Green mark? |
|---|---|---|
| Stainless steel | No | No. It carries no copper |
| Sterling silver | Yes, to a dark film | No, though sterling contains some copper |
| Brass or bronze | Yes | Yes, once worn against skin |
| Copper | Yes, quickly | Yes |
| Solid karat gold | No | No |
Green marks are copper salts, formed when copper in an alloy meets the salt and acid in sweat. The full explanation is in why jewelry turns your skin green.
The catch with plated steel
Most gold-coloured steel jewelry is steel underneath a gold finish, and the finish is the part that wears. The FTC states it plainly: “Eventually, the gold plating wears away, depending on how the item is worn and the thickness of the plating.” (FTC consumer guide)
What matters is what is revealed when it does. On a steel base, a worn patch shows steel, which does not tarnish and does not mark skin. On a brass base, the same wear exposes copper alloy, which does both. Identical pieces on a product photograph, different outcomes in a year.
What to ask before buying
- What is the base metal? Steel, brass or sterling. A listing that names the plating but never what it sits on has answered the question by not answering it.
- Which grade of steel? Grades differ. 316L is the one commonly used where corrosion resistance matters.
- Has nickel release been tested? Steel alloys contain nickel, and nickel is the metal behind most jewelry contact dermatitis. The test, not the material name, is the answer.
Where SIAFRA stands
Specified as 18K gold PVD over stainless steel rather than brass, for exactly the reason above. The grade is being confirmed with the supplier, nickel release testing is scheduled, and both will be published on the specifications page before anything ships. Until the report exists, the base metal is a specification rather than a result.
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