Silver Agate
Sterling SilverSterling silver, also called fine silver, is a beautifully lustrous cool-toned precious metal favored in fine jewelry among other products. The most reflective of all metals (excluding mercury), sterling silver looks stunning by itself and brings out the best hues in an array of colorful gemstones.
Sterling silver can be polished to a higher sheen than platinum. In fact, Ag, the chemical symbol for silver, comes from a word that means “white and shining.” The surface of silver can boast that shiny, polished appearance, or can be brushed, satin, matte, sandblasted, antiqued or oxidized (chemically blackened).
In order to be called sterling silver, a metal must be made up of a minimum of 92.5% pure silver and 7.5% alloy (meaning other metals), including but not limited to copper and nickel. The alloy is added to pure silver to make the metal more durable, tougher and harder. Sterling silver is designated a fineness of “925.” Pieces with sterling silver may be marked “sterling.”
Finishes on Sterling Silver
Finishing, or plating, is a common treatment with sterling silver. Popular types of plating are rhodium plating, gold plating and anti-tarnish plating. Plating is used to extend the life and sheen of the jewelry. After sizing or buffing a piece of jewelry with a machine, it must be re-plated to restore the finish.
Rhodium Plating: Rhodium plating is a complex and laborious process that enhances the luster and beauty and extends the life of silver. A member of the platinum metal group, rhodium is often used as a finishing touch on silver jewelry. It's a shiny silvery metal with a very white and reflective appearance, much like mercury. It's also very hard, so it withstands much wear and tear, resists natural tarnishing and wonderfully mimics the brilliant finish of freshly polished silver.
Platinum Plating: Platinum plating is comprised of an 80 mils layer of platinum plated over sterling silver, followed by a layer of rhodium.
Endicron Plating: Endicron plating is one micron of white gold plating followed by a layer of rhodium. With this plating, durability is improved and the metal looks and feels more like gold or platinum.
White Lustre™ Plating: This is a platinum-derived rhodium plating that mimics the reflective mirror quality and color of platinum. This type of plating is durable and highly resistant to tarnish.
Evershield Plating: Evershield plating is comprised of an 80 mils layer of gold plated to the sterling silver.
Vermeil Plating: Pronounced “vermay,” vermeil gold is the way heavy 14K or higher gold that is electroplated over sterling silver is officially designated by the industry. Items may only be marked or sold as vermeil if they have a minimum thickness of 100 millionths of an inch of gold or 2.5 microns of gold.
Caring for Sterling Silver
Sterling silver becomes tarnished as the result of a natural chemical process that occurs when sterling silver is exposed to chemicals in the air, rubber, wool and latex. Humidity also plays a role in accelerating tarnishing. It's easy to keep your sterling silver sparkling, though, by taking a few steps to prevent tarnish and other wear and tear.
Avoid exposing sterling silver to direct sunlight and harsh chemicals, including chlorine, ammonia, hair products, perfumes, cosmetics, perspiration and strong jewelry cleaning solutions.
Periodically wash sterling silver with mild dish soap and warm water. Rinse well and dry completely with a soft cloth before storing because moisture can cause tarnish.
Lightly polish sterling silver frequently with a soft silver-polishing cloth, avoiding abrasive cloths completely.
Tarnish is easy to remove when it first forms as a yellowish tint, but becomes more difficult to remove when it becomes brown and black. Remove tarnish with a silver polish cream, avoiding immersing pieces with gemstones in tarnish-removal solutions.
Minimize scratches on sterling silver by storing it in its own compartment in your jewelry box or in a cloth pouch. Sterling silver may also be stored in sealed polyethylene bags.
Agate: Found all over the world, agate has been creatively striped by nature. It is a type of chalcedony quartz that forms in concentric layers of colors and textures. Each individual agate forms by filling a cavity in a host rock. As a result, agate often is found as a round nodule with concentric bands like the rings of a tree trunk. Tiny quartz crystals called druzy (sometimes spelled as drusy) often form within the stone, adding to its beauty and uniqueness. Agate is a hard stone, within the range of 7.0-9.0 on the Mohs Scale.
In 1497, the mining of agate in the Nahe River valley in Germany gave rise to the cutting center of Idar-Oberstein. When the Nahe agate deposit was exhausted in the nineteenth century, Idar cutters started to develop the agate deposits of Brazil, discovering Brazil's rich deposits of many other gemstones. A famous collection of two to four thousand agate bowls, accumulated by Mithradates, King of Pontus, shows the popularity of agate at the time. Agate bowls were also popular in the Byzantine Empire. Collecting agate bowls became common among European royalty during the Renaissance and many museums in Europe, including the Louvre, have spectacular examples.
Although the small town of Idar-Oberstein is still known for the finest agate carving in the world, today Idar imports a huge range of other gem materials from around the world for cutting and carving in Germany. Cameo master carvers, modern lapidary artists and rough dealers flourish there, exporting their latest gem creations. It is an entire industry that grew from the desire for agate products during the Renaissance.
Agate was highly valued as a talisman or amulet in ancient times. It was said to quench thirst and protect from fevers. Persian magicians used agate to divert storms. Today, some believe that agate is a powerful emotional healer and helps people discern the truth.
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