Although we can’t ascertain the origins of the word ’sterling’, when referring to silver, it only means one thing: an alloy of silver containing 92.5% by weight of silver. This means that sterling includes other metals. Since 92.5% is silver, 7.5% is something else, usually copper.
Like Gold, Silver in its 100% pure form is generally considered too soft for making large or functional items. Silver is usually mixed with copper to make it stronger. Mixing with copper also allows silver to maintain its flexibility without breaking as well as its beauty. One drawback, though, is that adding copper or other metals often cause silver to tarnish. Pure silver does not easily tarnish, but when mixed with copper, silver is found to tarnish much more easily. When silver is mixed or ‘alloyed’ with copper, it is also vulnerable to turning purple in some spots. This is called firestain or firescale. So, some people choose to alloy their silver with germanium, zinc and platinum. Silicon and boron are also used to mix with silver. The most successful, and therefore, the most popular alloy of recent years is called Argentium sterling. It is named after a company in the U.K. that created it. It has been found to be extremely effective in eliminating firescale and the necessity to coat the silver with something to prevent tarnishing.Oddly enough, the silver itself is not the problem with tarnishing. As the purity of the silver decreases, the tendency to tarnish becomes worse. Chemically, silver is not very reactive—it does not react with oxygen or water at ordinary temperatures, so does not easily tarnish. However, other metals in the alloy, usually copper, may react with oxygen in the air. This reaction has caused the copper Statue of Liberty to turn green. Salt water doesn’t help. Sodium chloride (common table salt) is known to corrode silver-copper alloy, typically seen in silver salt shakers where corrosion appears around the holes in the top.
What about silver jewelry? Nowadays, much silver jewelry is plated or coated with something to prevent and almost completely eliminate tarnish. Beautiful bracelets, rings, necklaces and many other items are available that keep their beautiful silver shine without tarnishing. Sterling silver jewelry is also modestly priced and many pieces can be found that most budgets will allow. So, if you’re looking to own silver jewelry but are concerned about tarnish or firestain, there’s no need for concern. It’s easy to find a large selection of fine jewelry that will maintain their luster for many, many years to come.
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