Ads
related to: raw peridot stones for sale
Search results
Results From The WOW.Com Content Network
Peridot. Peridot (/ ˈpɛrɪˌdɒt, - ˌdoʊ / PERR-ih-dot, -doh), sometimes called chrysolite, is a yellow-green transparent variety of olivine. Peridot is one of the few gemstones that occur in only one color. Peridot can be found in mafic and ultramafic rocks occurring in lava and peridotite xenoliths of the mantle.
Demantoid is the green gemstone variety of the mineral andradite, a member of the garnet group of minerals. Andradite is a calcium - and iron -rich garnet. The chemical formula is Ca 3 Fe 2 (SiO 4) 3 with chromium substitution as the cause of the demantoid green color. Ferric iron is the cause of the yellow in the stone.
Hiddenite. Hiddenite is a pale-to-emerald green variety of spodumene that is sometimes used as a gemstone. The first specimens of the hiddenite variety of spodumene were recovered circa 1879 near the settlement of White Plains, west of Stony Point, Alexander County, North Carolina. According to contemporary accounts, a man named Lackey brought ...
Opal is a hydrated amorphous form of silica (SiO 2 · n H 2 O); its water content may range from 3% to 21% by weight, but is usually between 6% and 10%. Due to its amorphous property, it is classified as a mineraloid, unlike crystalline forms of silica, which are considered minerals. It is deposited at a relatively low temperature and may occur ...
In 1979, Gemstones Corporation of Pakistan was established to develop the gemstones sector in Pakistan, however in 1997 the corporation liquidated. [3] Now a number of organizations are working in this sector including All Pakistan Commercial Exporters Association of Rough & Unpolished Precious and Semi Precious Stones (APCEA) and Pakistan Gems and Jewellery Development Company (PGJDC).
Emerald is a gemstone and a variety of the mineral beryl (Be 3 Al 2 (SiO 3) 6) colored green by trace amounts of chromium or sometimes vanadium. [2] Beryl has a hardness of 7.5–8 on the Mohs scale. [2] Most emeralds have many inclusions, [3] so their toughness (resistance to breakage) is classified as generally poor.