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
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
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.
Cubic zirconia is the most readily available, inexpensive and brilliant simulated diamond on the market today. Cubic zirconia does occur naturally in small quantities, but all of the cubic zirconia on the market is produced in a laboratory.
On the Mohs Scale, which measures the hardness of minerals, cubic zirconia is an 8.0 to 8.5. It is important to understand that hardness is not necessarily related to durability. Even though diamond is the hardest mineral (10.0 on the Mohs Scale), it can still be chipped or broken.
The only ways to tell the difference between cubic zirconia and diamond are by use of a thermal probe, by weighing the loose stone or by microscopic examination of surface features and inclusions. Cubic zirconia weighs approximately 65% more than diamond. Therefore, while a 6.25 mm round diamond weighs about 1.00 carat, the same size cubic zirconia weighs about 1.65 carats. If you know the weight of a cubic zirconia, you can figure out the diamond weight equivalent by multiplying the cubic zirconia weight by 0.6, or 60%.
Few natural diamonds on the market today are perfectly cut, and those that are cost much more than the usual diamond. Unleashing the fire, beauty and brilliance of a stone depends on its precise cut. Simulated diamonds are an excellent balance between quality, beauty and price.
Brilliance: The white light leaving a jewel, traveling upward, which is visible to the eye. Brilliance is sometimes referred to as “sparkle.”
Dispersion: Flashes of rainbow colors. Also called “fire.”
Hardness: Resistance to scratching. The higher the number, the more resistant.
Luster: The shininess of a jewel.
Toughness: Resistance to breakage.
Earring Back Types
Butterfly Back: A double looped piece resembling a butterfly that fits over a post. Variations on this design are called push back clasps. The basic post and butterfly back are usually used for stud earrings and lighter weight drop earrings.
Hinged Snap Backs: This clasp features a hinged post that snaps into a groove on the back of the earring. It is commonly found on hoops. Sometimes the hinged post is curved to provide more room to fit around the ear, sometimes called a saddleback.
Hook Backs: This earring backing is simply a long, bent post that fits through the piercing. Hooks have several variations, most notably the shepherd's hook and the French hook. While thin wire hooks reduce the weight of long earrings, making them more comfortable, they aren't as secure as other clasp styles.
Lever Back: A hinged lever snaps shut against the curved post to form a closed loop around the ear lobe. This clasp is very secure and good for large or medium sized styles that drop just below the ear.
Omega: Also called French clips, this clasp has a straight post and a looped lever. The hinged lever closes around the post and is held against the ear with pressure. The omega clasp is the most secure clasp, especially for the larger, heavier earrings.
Screw back: This backing is a slight variation of the standard post and butterfly nut back. Instead of pushing on the back, the nut twists onto the threaded post. A screw back post design is often preferred for expensive diamond stud earrings that require increased security.