Yes, copper jewelry can change color over time.
Copper is a reactive metal that undergoes oxidation when exposed to air and moisture. This process causes the surface of the copper to tarnish, resulting in a color change. Initially, the jewelry may darken from its original bright, shiny color to a deeper brown, or a golden brown.
Over time, and especially without regular cleaning, copper jewelry can develop a greenish patina, due to the formation of copper oxides, sulfides, and carbonates on its surface. This green patina is a protective layer and is often desired in certain aesthetic applications, but it might not be preferred for jewelry.
Here's a summary of the color changes copper jewelry can undergo:
- Original: Bright, shiny copper color.
- Initial Tarnish: Darker brown or golden brown.
- Further Tarnish (with exposure and lack of cleaning): Greenish patina.
A simple polishing cloth will not remove a heavy patina. More aggressive cleaning methods are needed to restore the original color.
