Nephrite
Gemstone
Nephrite is a variety of the calcium, magnesium, and iron-rich amphibole minerals tremolite or actinolite. The chemical formula for nephrite is Ca₂(Mg, Fe)₅Si₈O₂₂(OH)₂. It is one of two different mineral species called jade. The other mineral... Wikipedia
Hardness (Mohs hardness scale): 6 – 7
Chemical formula: Ca₂(Mg,Fe)₅Si₈O₂₂ (OH)₂
Density: 2.9-3.03
Birefringence: usually not detectable
Category: Inosilicate
Crystal habit: massive