Sterling 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
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.
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.
Caring for Sterling Silver
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.
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.
A relative newcomer to the gem world, ametrine is a variety of quartz that exhibits the best aspects of both purple amethyst and yellow citrine within the same crystal. These bicolor yellow and purple quartz gemstones have a hardness of 7.0 on the Mohs Scale and are ideally suited for a variety of jewelry uses.
Ametrine is most typically faceted in a rectangular shape with a 50/50 pairing of amethyst and citrine. When cut into emerald and pear shapes, the color distinction is most notable. Sometimes a checkerboard pattern of facets is added to the top to increase light reflection. Ametrine can also be cut to blend the two colors so that the resulting stone is a mix of yellow, purple and peach tones throughout the stone. When ametrine is fashioned as the less-common brilliant round shape, its colors reflect and blend together to create the peach-like color.
Ametrine is especially popular among artistic cutters and carvers who can play with the colors, creating landscapes in the stone. Amethyst's purple and citrine's yellow are opposite each other on the color wheel. They are called complementary colors, meaning that they enhance each other, and are considered by artists to be excellent colors to use together. Because its beauty lies in the coexistence of the two colors, ametrine is usually recovered in larger sizes; over five carats is most popular, which allows for the appreciation of the pronounced color contrast.
The Anahi Mine in Bolivia is the major world producer of ametrine. The mine first became famous in the seventeenth century when a Spanish conquistador received it as a dowry upon marrying a princess from the Ayoreos tribe, named Anahi. Ametrine was introduced to Europe through the conquistador's gifts to the Spanish queen. The stone is relatively inexpensive, considering that it comes from only a few mines in the world, including Bolivia and Brazil. Several suppliers have indicated that the ametrine mines have run out, and therefore quality material is now very difficult to obtain.
As a newcomer, ametrine does not yet have folklore or historical significance attached to it, as do amethyst and citrine. Some sources believe, however, that the best aspects of amethyst and citrine lore should be attributed to ametrine since it is a combination of both gems.