Lapis Lazuli Birthstone Wedding Fashion 2014 Jewellery In American Samoa 04

 Lapis Lazuli Birthstone Wedding Fashion 2014 Jewellery In American Samoa.

 By Aamir Mannan

Lapis lazuli is a rock whose most important mineral component is lazurite[9] (25% to 40%), a feldspathoid silicate mineral with the formula (Na,Ca)8(AlSiO4)6(S,SO4,Cl)1-2.[10] Most lapis lazuli also contains calcite (white), sodalite (blue), and pyrite (metallic yellow). Other possible constituents: augite; diopside; enstatite; mica; hauynite; hornblende, and nosean. Some lapis lazuli contains trace amounts of the sulfur-rich löllingite variety geyerite.

Lapis lazuli usually occurs in crystalline marble as a result of contact metamorphism.