Nephrite Jade
Amphibole
Amphiboles are double chain silicates
Unlike pyroxenes, amphiboles are Hydrous minerals (contain hydrogen)
Cleavages are at 60 Degrees
Composition : Ca2(Mg,Fe)5Si6O22(OH)
Green color is due to Iron (Fe)
Resembles jadeite in color and structure
Hardness - 6.0 to 6.5
Harder and tougher than steel
Occurs in rocks subjected to low-grade metamorphism
Jadeite Jade
Part of the pyroxene family. Pyroxenes are silicate minerals. The simplest formula is MgSiO3.
Forms single chain silicates
Cleavages are at 90 Degrees
Composition: NaAISi2O6
Deep green color is due to presence of Chromium (Cr) Iron produces paler green color
Hardness - 6.5 to 7.0
Harder and tougher than steel
Formed by high pressure metamorphism of Sodium rich rocks. (NA)
Nature of Jade III