Chemical bath turns copper and silver jewelry black

• Oxidation is a natural process that causes metals to tarnish, visibly changing their color.
• Jewelers use liver of sulfur to chemically oxidize jewelry, giving it a black finish.
• The process works on many metals but is commonly applied to copper, since it quickly tarnishes.

Oxidation is a process in which elements lose electrons. When this happens to metals, their color tarnishes, resulting in a visible change. Common jewelry metals like copper and silver will oxidize, but copper is quicker to. By chemically oxidizing the metal in a liver of sulfur bath, jewelers force this color-changing process to happen on their terms. The process can transform both copper and silver from their original hues to nearly black. By doing this, jewelry is prevented from unevenly blemishing over time, and an even, long-lasting color is achieved.