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The famous Tiffany symbols: the little blue box, the engraved T&Co., 1837 and 925. But what is 925? The 925 engraving on a Tiffany product represents the item as sterling silver, since the percentage grade of the American Sterling Silver Standard is 925. It's a standard that was pioneered in the United States by none other than Tiffany & Co. itself.

Sterling Silver

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The compound ratio of metals to silver by weight that makes up standard sterling silver is 92.5 percent silver to 7.5 percent metal, hence sterling silver is 925/1000 proof silver. It is to this that the Tiffany mark of 925 refers to, signifying that all Tiffany & Co. silver products meet the American and British Sterling Silver Standard in grade. Because of the extremely malleable properties of silver, other metals, such as copper, must be added to achieve a practical strength. Thus sterling silver is not a pure or "fine silver," but it is instead an alloy.

History of Sterling

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The sterling silver standard (the 925 ratio) first originated in England around the 14th century, when King Edward I declared it mandatory for all silversmiths to manufacture silver products with 92.5 percent pure silver. The name "sterling standard" derived from the term for the contemporary British silver penny, known as a starling in reference to its visual property of "shining like the stars," starling literally meaning "little star."

Starling silver was thus coin silver proof, 925 pure silver parts per 1,000. There are a few countries whose sterling standard is lower than 925, though in the United States sterling 925 was adopted as the the American standard in the late 19th century after the popular use of the British standard by Tiffany & Co.

History of T&Co.

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Tiffany & Co. was founded in 1837 by Charles Tiffany and John B. Young. Four years later, the duo was joined by J.L. Ellis, and the company became known as Tiffany, Young & Ellis and took off as a fine jewelry and silver merchandise retailer. In 1851, Tiffany, Young & Ellis became the first silver company in America to market their products as British standard sterling 925 grade to give the company an edge over the competition. The young company contracted with the New York silversmith firm of John C. Moore to ensure control over the 925 grade.

Young and Ellis retired from the jewelry business in 1853, leaving complete control to Tiffany. In 1867, Tiffany & Co. became the first American firm to win the award for excellence in silver at the Exposition Universelle in Paris. One year later, Tiffany bought Moore Silver and became both retailer and manufacturer of Tiffany silver.

Tiffany's 1837 Collection

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The Tiffany 1837 collection is a series of engraved silver and gold pieces that includes rings, pendants, earrings, charms, necklaces and bracelets engraved with "T&Co." "1837" and the "925" mark on the silver, and "750" mark on the gold. The 1837 collection is considered on of the hallmark classic collections of Tiffany & Co.

Tiffany Today

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Today Tiffany & Co.'s iconic blue box is known the world over as a symbol of one of the United States' premier jewelry companies. Because of the high quality and popularity of Tiffany silver, the U.S. adopted the British 925 sterling standard as the American sterling standard that remains to this day.

About the Author

Mallory Ferland

Mallory Ferland has been writing professionally since her start in 2009 as an editorial assistant for Idaho-based Premier Publishing. Her writing and photography have appeared in "Idaho Cuisine" magazine, "Spokane Sizzle" and various online publications. She graduated from Gonzaga University in 2009 with Bachelor of Arts degrees in history and French language and now writes, photographs and teaches English in Sao Paulo, Brazil.