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What is Sterling Silver
Fine silver (99.9% pure) like most precious metals, is very malleable (easily bent and deformed) and too soft for producing functional objects and jewelry. Bracelets, rings, earrings, pendants, dogtags and other forms of silver jewelry cannot possibly be made from pure silver. Therefore, pure silver is alloyed with copper to increase its hardness without affecting the ductility and beauty of the precious metal. However, as the purity of silver decreases, the problem of corrosion or tarnishing increases, creating the need to find a balance between the percentage content of Silver and the cheaper metal used in the alloy couple.
The solution, as discovered by the globe’s most brilliant chemists, is sterling silver: an alloy of silver containing 92.5% by mass of silver and 7.5% by mass of other metals, usually copper. The sterling silver standard has a minimum millesimal fineness of 925 (ie: 92.5% purity). Given the high percentage purity of sterling silver, sterling silver is commonly used in the manufacture of jewelry and high grade luxury cutlery used by royalty.
Chemically, silver is not very reactive—it does not react with oxygen or water at ordinary temperatures, so does not easily form silver oxide. However, other metals in the alloy, usually copper, may react with oxygen in the air, tarnishing the overall appearance of the sterling silver alloy. The good news, however, is that tarnish is easily reversible by polishing: a process which removes the surface coat of copper oxide obscuring the brilliant sheen of the underlying alloy. The easy reversibility of the tarnish has made sterling silver jewelry the gold standard of consumer choice in silver jewelry craftsmanship.
Sterling Silveris an alloy of 92 1/2 percent silver and 7 1/2 percent copper. Its beauty increases with use, which causes a patina or soft sheen to form. Plated silver is silver that has been electroplated over another metal. Silver tarnishes when exposed to air. This occurs more quickly in damp and foggy weather, but is inevitable in any climate. Store in treated paper or cloth, or plastic film.
Methods of cleaning silver should be determined by the value placed on it, monetary or sentimental, and the design of the pattern. Silver with deeply "carved" patterns that are enhanced by an oxide or French gray finish should be hand polished with a high quality silver cream or polish.
Hand rubbing develops patina on silver which adds to its beauty. Ornamental silver pieces that have been lacquered may be washed in lukewarm water; hot water could remove the lacquer. Polishing silver while wearing rubber gloves promotes tarnish. Instead, choose plastic or cotton gloves.
Silver has enemies. Rubber severely affects silver. Rubber corrodes silver, and it can become so deeply etched that only a silversmith can repair the damage. Raised designs can be lost permanently. Avoid using storage cabinets or chests with rubber seals, rubber floor coverings, rubber bands, etc.
Other enemies of silver include table salt, olives, salad dressing, eggs, vinegar and fruit juices. Serve these foods in china or glass containers. Although flowers and fruit look lovely in silver containers, the acid produced as they decay can etch the containers and cause serious damage. When using silver containers, use plastic or glass liners.
Baking Soda: Apply a paste of baking soda and water. Rub, rinse, and polish dry with a soft cloth. To remove tarnish from silverware, sprinkle baking soda on a damp cloth and rub it on the silverware until tarnish is gone. Rinse and dry well.
Aluminum Foil, Baking Soda, and Salt: Place a sheet of aluminum foil in the bottom of a pan, add 2-3 inches of water, 1 teaspoon baking soda, 1 teaspoon salt, and bring to a boil. Add silver pieces, boil 2-3 minutes, making sure the water covers the silver pieces. Remove silver, rinse, dry, and buff with a soft cloth. This method cleans the design and crevices of silver pieces.
Toothpaste: To clean off tarnish, coat the silver with toothpaste, then run it under warm water, work it into a foam, and rinse it off. For stubborn stains or intricate grooves, use an old soft-bristled toothbrush.
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