Jade (Nephrite)
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Mineral NameJade (Nephrite)
Chemical FormulaCa₂(Mg,Fe²⁺)₅Si₈O₂₂(OH)₂
Mohs Hardness6
Crystal Systemmonoclinic
Streak Colorwhite
Cleavageperfect on {110}, but rarely observed due to fibrous habit
Fracturesplintery to conchoidal
Specific Gravity2.95
Colorsdark green, olive green, grayish green, white, cream, yellow, brown, black
Transparencytranslucent to opaque
Type LocalityLander County, Wyoming
Mineral GroupSilicates (Amphibole group)
Usesjewelry, carving material, ornamental objects, tools
Associated Mineralsserpentine, chlorite, talc, magnetite, chromite, garnet
Rarityuncommon
Description
This specimen is a dark olive-green to grayish-green, compact mass with a somewhat mottled appearance and a dull to slightly greasy luster. It exhibits the characteristic tough, interwoven fibrous texture of nephrite.
Geological Context
Nephrite forms primarily through the metamorphism of magnesium-rich rocks such as serpentinites or dolomitic limestones, often in contact metamorphic zones or regional metamorphic terrains. It is a variety of the amphibole minerals tremolite-actinolite.
