The Original of Peridot
2017-07-19
Peridot is an intermediate variety of the Mg2Sio4 and Fe2Sio4 series. Name of common green olive of various magnesium.
Peridot is named for its olive green color. Its English name is PeridotOlivine, the former directly from the French Peridot, and the latter is a mineralogical noun. Ancient Rome philosopher Pliny once used the word "CHRYSOLITE", this word is from the Greek, "gold" and "jewel", is used to describe the Citrine, topaz, but today, yellowish green and yellow green emerald is often used in europe. Emerald is an island structure of silicate minerals, chemical formula 2[Sio4] (Mg, Fe), usually made of magnesium and iron (Forsterite) Mg2Sio4 emerald emerald (Fayalite) Fe2Sio4 mixture. Orthorhombic system. In the iron rich members, sometimes a small amount of Ca2+ and Mn2+ replacement of Fe2+, while the magnesium rich members can have a small amount of Cr3+ and Ni2+ replacement, in which Mg2+ can also contain trace amounts of Fe3+, Zn2+ and so on.
The crystal morphology is usually short columnar, and the aggregate is irregularly granular. The colour is pure magnesium; the emerald is colorless to yellow; the iron green is greenish yellow; brown or brown when oxidized. Mostly olive green, yellow green, golden green or grandmother green. Grease, gloss, transparency. 1.6541.690 refractive index, birefringence 0.0350.038, so under a magnifying glass, bottomthe emerald will have a double shadow. Chromatic diversity is not obvious, chromatic dispersion 0.020. The hardness of 6.57.0, proportion of 3.273.48. With shell fracture, toughness is poor, cracks are easy to occur. The most similar emerald mineral is sinhalite (Sinhalite), which is a dark brown or greenish brown orthorhombic mineral component is Mgaibo4. Its proportion is 3.47 to 3.49, the refractive index of low, medium and high values are 1.668, 1.699 and 1.707.
