Gold Jewelry Tarnished: Causes and Solutions
Gold jewelry turning dark – that sounds contradictory. Gold does not oxidize, so why is my gold chain turning dark? There are several explanations, and each has a different solution. This guide explains all the causes of gold jewelry discoloring.
Cause 1: It's not real gold
The most common reason: The jewelry is not made of real gold, but of gold-plated metal (brass, zinc, copper) with a thin layer of gold. When this gold layer wears off, the underlying metal becomes visible – and that oxidizes. Green or black spots on "golden" pieces are almost always gold-plated non-gold jewelry. Solution: Material testing. Does the piece have a "585" or "750" stamp? If not, it's likely not real gold.
Cause 2: Tarnishing due to sulfur compounds
Real gold usually does not react with air. However, gold alloys contain copper and silver. Silver is the prime candidate for tarnishing – and white gold often contains it in larger quantities. Sulfur compounds in the air (city air, proximity to industry, some foods) can cause tarnish spots on white gold jewelry. Yellow gold is less affected; white gold somewhat more. Solution: Gold polish or professional cleaning by a jeweler.
Cause 3: Chlorine reaction
Chlorine from swimming pools reacts with gold alloys and can cause permanent chemical changes. Regular swimming with gold jewelry often leads to a "grayed" or cloudy appearance. Solution: Remove gold jewelry before swimming. Existing chlorine damage: Jeweler cleaning and polishing.
Cause 4: Mercury contact
Mercury (in some old thermometers, certain batteries, industrial processes) reacts with gold and forms an amalgam that permanently blackens the gold. This is rare – but irreversible without jeweler intervention. Solution: A jeweler can often remove the affected metal and re-polish it.
Cause 5: Gold plating wears off (normal process)
For gold-plated jewelry, darkening is normal and expected: The gold layer wears off, and the base metal appears. This is not a defect – it is the natural life cycle of gold-plated jewelry. Solution: Re-plating by a jeweler (20–40 €) or replacing the piece with a new one.
Cleaning tarnished gold jewelry
- Light tarnishing: Dish soap bath (lukewarm water + a drop of mild dish soap, 10 min, soft brush, rinse)
- Heavier tarnishing: Gold polishing cloth from the jeweler
- Stubborn discoloration: Jeweler – ultrasonic cleaning and professional polishing
Genuine durable gold at Corelune Jewellery
Materials that deliver on their promises – at Corelune Jewellery you will find jewelry with clear specifications.
