Silver can rust or tarnish over time because of exposure to moisture or sulfur in the air. Tarnish and rust can cause silver to darken and look like it is black. More »

Rust forms on iron due to an oxidation reaction that occurs when it comes into contact with oxygen and water. The reaction of iron, oxygen and water forms hydrated iron(III) oxide, which is known as rust. Acid rain or sa... More »

A rust inhibitor is a type of substance or chemical compound that reduces the rate of oxidation. It also helps prevent early rust damage from occurring. More »

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Silver tarnishes due to a reaction with sulfur in the air. Moisture and sunlight can also cause tarnish. More »

Sterling silver turns black or tarnishes due to a chemical reaction caused by contact with sulfur or hydrogen. Some foods or everyday items containing sulfur can cause tarnishing, but even polluted air can turn sterling ... More »

Hydrogen sulfide gas in the air causes silver jewelry to tarnish. This process happens quickly when silver jewelry is left out in the open, unprotected by a jewelry box. Tarnished silver jewelry turns a person's skin bla... More »

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All silver, plate, fill, sterling and fine tarnishes when its alloy metal, copper, is exposed to chlorides and sulfurs in the air. Argentium sterling silver is the most tarnish resistant because it contains more pure sil... More »