PERIDOT also called Chrysolite and Olivine
Birthstone: August
Moh's hardness: 6.5-7
Density: 3.28-3.48
Color: Yellow-green, olive-green, brownish
Chemical Composition: (Mg,Fe)2SiO4
Refractive Index: 1.650-1.703
Peridot is the best known gem variety of olivine, a species name for a series of magnesium-iron rich silicate minerals. This bright yellow-green to green to a brownish colored gemstone has caught the fancy of humans for thousands of years. Some historians even think that at least some of the "emeralds" worn by Cleopatra were actually peridot! Much of its recent popularity can be explained by its currently being recognized as the birthstone for the month of August, people wear the stone because it is supposed to bring the wearer success, peace, and good luck.
The United States was for many years the largest producer of peridot, the value of production in 1993 was estimated to be about $1.5 million, according to the USBM. Now a days, the United States is getting major Competition from China and Pakistan for the title of world's largest producer. Arizona and New Mexico produce the largest supply of peridots in the US.
Historically important deposit was on the Red Sea volcanic island Zabargad (St. John), 188 miles east of Aswan Egypt; it was mined for 3500 years but forgotten for many centuries and rediscovered only around 1900. Most of the earliest known peridot gems came from this location and small amounts of material are still being produced from there today. Later, very large, fine-quality peridot was produced from deposits in Myanmar (formerly Burma). These deposits were well known for their 20- to 40-carat cut stones of superb color and clarity, but since the socialist government came to power, the supply of Burmese peridot has been curtailed to such a point as to no longer be a factor in the industry. One can only guess as to whether the deposits are mined out, or if government policies have resulted in the shortage of material.
No comments:
Post a Comment