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5 Things That Cause Tarnish

Tarnish is the patina or layer of residue that accumulates on metals like copper, brass and silver. Jewelry, cutlery and other items become tarnished over time due to a variety of factors, depending on the metals the items are made of and how they are stored and cared for. Usually, the tarnish is black, gray or green.

Exposure to Air
- Simply being exposed to the air can cause tarnish over time. Metals (such as silver) react with the oxygen and other elements in the air, especially sulfur compounds.
Cosmetics and Body Care Products
- Cosmetics or other products on skin that rub off when you touch the metals, especially jewelry and silverware, cause tarnish. Metals present in makeup are often abrasive over time to silver, brass, or copper.
Moisture
- Moisture from water, perspiration or other liquids can cause tarnish. Jewelry in contact with water and sweat may tarnish more quickly than if it is kept dry.
Abrasion
- Rubbing or touching a metal often will cause tarnish. Rubbing your silverware or jewelry against other items ̵2; especially other metals ̵2; without wiping them off or cleansing them properly will increase tarnish over time.
Salt
- Although it might not be visible, salt causes corrosion of stainless steel. Hard water contains high amounts of salt that can cause tarnish.

Rocks & Minerals