Nephrite

Nephrite in pure form is white in color or else green or creamy white. Sometimes even beige, yellow, blue or black is seen. It is a variety of jade, chiefly a metasilicate of iron, calcium, and magnesium. The green color in nephrite is due the presence of iron. Physically it is similar to chalcedony. Both have a fibrous structure.

Nephrite is used as jewelry, carvings and bowls and vases. It is one of the longest wearing of any gem material. The toughness of the stone made ancient cultures to use it for symbolic ornaments, axes, knives and weapons. It is also said, related to the burning of old jewelery, the only object which survived the fire were the expensive nephrite carvings.

Canada, USA, Mexico, and Australia are the major world producers of nephrite. It is also found in China and New Zealand. The specific gravity of nephrite is 3 and hardness is 5.75 on Mohs scale.

Techinical Specification

Name	Moh's	Specific Gravity	Structure	Cleavage	Refractive Index	Double	Disp.	Pleochro	Fluorescence
Nephrite	6+	2.90-3.02	Monoclinic	Lengthwise perfect	1.600-1.627	-0.027 to none	None	Weak	None