This gemstone is also known as Olivine, because of its olive green coloring. The Peridot is a magnesium iron silicate that comprises two minerals: fayalit and forsterite. Fayalite is iron rich and Fosterite Magnesium rich.
The ideal color of Peridot is a rich green, but some Peridots are yellowish green, greenish yellow or brown. Iron gives the Periodot is green coloring although the best colored gemstones have an iron percentage of less than 15% as more than that starts to create a brownish coloration. Chromium, that adds blue to a gemstone and Nickel, as trace elements, contribute to the best peridot color.
peridot is one of the few gemstones found in only one color. This is because Peridot comes from its basic chemical composition and not from minor impurities, therefore it will only be found in shades of green.
On the Mohs scale of hardness, the Peridot only scores 5.5 – 7 and care should be taken when wearing this gemstone, to avoid scratching the surface.
Some inclusions can be found in Peridots although it is commonly a transparent stone. Table and step cuts are popular, although brilliant cuts work well when they are set in gold to create a sparkling contrast of colors. Peridots, like emeralds, are sometimes “oiled” or treated with natural or synthetic resins to disguise surface fractures and to improve luster.
Rare gemstones are Peridot Cat’s Eye and the Star Peridot that has four rays of light.
Peridots are found mainly in Pakistan and the Pakistan-Afghanistan border. The gemstone has also been found in basalts on the moon.