Gemstone Spotlight: Peridot
Peridot is a member of the forsterite-fayalite family and is idiochromatic, which means that its coloration is the result of a chemical composition as opposed to impurities. It is found primarily in green although it can sometimes appear in shades that range from light yellow to brownish green.
Peridot is an ancient gem, having been recorded as far back as 1500 B.C.E. The St. John volcanic island, which can be found near the Red Sea had one of the largest deposits, and as such was mined for millennia. In more recent times, the highest quality deposits have been found in Burma (Myanmar), although it can also be found in places such as Pakistan, China, Vietnam and the U.S. State of Arizona. It has also been discovered in meteors and even on the surface of the moon and Mars.
Chemically speaking, peridot is a silicate of iron magnesium and the color intensity is highly dependent on the presence of iron. There might also be trace amounts of chromium or nickel, but unlike other gems such as sapphires or diamonds, peridot is not very hard and therefore has little acid resistance. Rare peridot specimens contain a phenomenon called asterism (chatoyancy) where the gem will form a cat’s eye that appears as 4 ray stars. Peridot is most distinct for its powerful double refraction. Like other gemstones, peridot forms inside the crust of the earth, but at a much deeper depth inside the mantle. The crystals will be created in the magma and will move to the earth’s surface via volcanic or tectonic activity.
How To Shop For Peridot
Since peridot comes in a single color, its value is dependent on the depth and intensity of the coloration. It has outstanding transparency, although bigger stones may appear a bit cloudy due to inclusions. When peridot is polished and cut, it has a vitreous and classy luster. When purchased in jewelry form it will usually be faceted since jewelers prefer step and table cuts. It can also be purchased in the form of cushions, octagons, ovals and rounds. Always purchase peridot based on gem size and not its carat weight.
How To Wear And Care For Peridot
Peridot goes great with any green colored outfit. Although it is not the hardest gem, it is sturdy enough to be used in multiple applications. Peridot rings are quite popular, particularly in China, since new deposits have been found there, and it is ideal for both female and male jewelry. It is also the birthstone of August. Bracelets, bangles, earrings and brooches which use this gem are spectacular.
As with other gems, you want to avoid scratching it. It can burst under sufficient pressure so you will want to avoid using it in applications such as rings which are tension set, and it should not be exposed to extreme temperatures. It can be readily cleaned using water that is warm and soapy with a cloth that is soft.