LemonTrades
TL;DR
- Pure 24K gold doesn’t tarnish or rust. It barely reacts with air or water.
- Lower-karat gold can tarnish slowly, because it’s mixed with copper and silver. The lower the karat, the more likely it is.
- Gold-plated pieces don’t so much tarnish as wear through to the metal underneath.
- LemonTrades follows the gold price for you and tells you what moved it, and why, within seconds.
Gold’s refusal to tarnish is much of why people have prized it for thousands of years. But most gold jewelry isn’t pure gold.
| Type | Gold content | Will it tarnish? |
|---|---|---|
| 24K | 99.9% | No |
| 18K | 75% | Rarely |
| 14K | 58.3% | Occasionally, with sweat or chemicals |
| 10K | 41.7% | More likely |
| Gold-filled | Thick layer over brass | Slowly, over years |
| Vermeil | Layer over sterling silver | Yes, as the silver shows through |
| Gold-plated | Very thin layer | Yes, as the plating wears away |
Why gold doesn’t tarnish, but your jewelry might
Tarnish is a chemical reaction with oxygen or sulfur in the air. Gold is one of the least reactive metals, which is why ancient gold coins still shine and gold doesn’t rust. Copper and silver do react, and they’re what’s mixed into most gold jewelry.
Why does gold jewelry turn skin green?
Usually it’s the copper in the alloy reacting with sweat, lotion or soap. Black marks are often metal rubbing off from makeup or from the jewelry. It’s harmless and more common with lower karats and plated pieces. If you see it on a piece sold as high-karat gold, get it tested. See how to tell if gold is real.
How to clean tarnished gold
- Mix warm water with a little mild dish soap.
- Soak for 15 minutes.
- Brush gently with a soft toothbrush.
- Rinse and dry with a soft cloth.
Skip bleach, chlorine, and abrasive polish. Be gentle with plated pieces, and take stones to a jeweler. Plated jewelry can’t be cleaned back: it needs re-plating. See what is gold filled? and what is gold vermeil?.
Does tarnish lower the value?
Sources
- Royal Society of Chemistry: Gold
- FTC: Guides for the jewelry and precious metals industries (16 CFR 23)
Education, not financial advice. See our disclaimer.
