The chemical formula of Peridot is indicated by (Mg,Fe)2SiO4 or Magnesium Iron Silicate. Peridot is actually a gem variety of Olivine. The best quality Peridot has historically come either from Egypt or Myanmar. Perhaps Peridot has derived its name from the French word peritot, which means unclear. This is maybe due to the inclusions and cloudy nature of large stones. It could have been also named after the Arabic word faridat, which means gem. Peridot is a beautiful gemstone in its own right. It is also very widely popular. Peridot can be als fun to collect.

 

            Peridot is most commonly found in shades of green usually from yellow-green to greenish yellow color that can be more splendidly exhibited when specimens are evaluated under polarized microscopes used in the field of optical mineralogy. Peridot is usually found showing vitreous luster when viewed in reflected light of petrographic polarizing microscopes. The hardness measure of Peridot when specimen sample is evaluated using the Mohs scale method is usually 6.5 to 7. Peridot is also known to crystallize in the orthorhombic system of crystal formation. In optical mineralogy, this orthorhombic crystal system comprises crystals having three mutually perpendicular axes, of which all are of different lengths.

 

Peridot  is most commonly found leaving a white streak when specimen sample is rubbed on a white porcelain streak plate. The index of refraction of Peridot is usually ranging from 1.630 to 1.695. It also shows 0.037 birefringence. The cleavage is usually not discernible even when specimen is evaluated with the aid of polarized microscope. This gem variety Peridot comes from the ancient source of Zagbargad Islan in the Red Sea off the coast of Egypt, also in Myanmar, Pakistan, Brazil, Germany, Mexico, Australia and several areas in USA.