metamorphic
Nephrite Jade
Ca2(Mg, Fe)5Si8O22(OH)2 (Actinolite-Tremolite series)
Hardness: 6-6.5 on Mohs scale; Color: Sage green with dark inclusions; Luster: Waxy to greasy; Crystal structure: Monoclinic (fibrous/interlocking); Cleavage: Indistinct; Specific Gravity: 2.90-3.03.
- Hardness
- 6-6
- Color
- Sage green with dark inclusions
- Luster
- Waxy to greasy
Identified More metamorphic →
Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 6-6.5 on Mohs scale; Color: Sage green with dark inclusions; Luster: Waxy to greasy; Crystal structure: Monoclinic (fibrous/interlocking); Cleavage: Indistinct; Specific Gravity: 2.90-3.03.
Formation & geological history
Formed via regional metamorphism of magnesium-rich limestones (dolomites) or ultrabasic rocks. It is created under high pressure/low temperature conditions in subduction zones.
Uses & applications
Used extensively in jewelry, ornamental carvings, sculpture, and historically for durable tool-making due to its extreme toughness.
Geological facts
Nephrite is significantly tougher than steel because of its felted, interlocking fibrous structure. It has been used for over 5,000 years in China and by the Maori people of New Zealand.
Field identification & locations
Identified by its waxy luster, smooth 'soapy' feel, and resistance to scratching from steel. In the field, it is often found as river-worn cobbles in areas with serpentinite belts.
More like this
