Nephrite Jade
Nephrite (Tremolite-Actinolite series) · Semi-Precious Gemstone / Ornamental Stone
Crystal System
Monoclinic; typically aggregate with a felted, interlocking fibrous habit
Mineral Group
Silicates; Inosilicate (Amphibole group)
Chemical Formula
Ca2(Mg,Fe)5Si8O22(OH)2
Formation Process
Metamorphic: formed by the regional or contact metamorphism of magnesium-rich limestones (dolomites) or ultrabasic rocks
About This Crystal
Dense, tough, and translucent to opaque material with a waxy to greasy luster. Exhibits a dark spinach-green to forest-green color with visible splintery, conchoidal fractures and a matte surface texture in raw form.
Physical Characteristics
Color: Dark Green; Streak: White; Cleavage: None (due to interlocking structure); Fracture: Splintery to conchoidal; Specific Gravity: 2.90–3.03; Fluorescence: Generally inert
Optical Properties
Refractive Index: 1.606–1.632; Birefringence: 0.027; Pleochroism: Weak; Optical Nature: Biaxial negative; Phenomena: Rare chatoyancy in fibrous specimens
Hardness & Durability
Origin Region
British Columbia (Canada), New Zealand, Russia, and China; typically found in metamorphic zones
Hardness & Durability
Mohs Hardness: 6.0–6.5; Toughness: Exceptional (highest of any natural stone due to felted structure); highly stable for wear
Care & Maintenance
Wash with warm soapy water; avoid harsh chemicals and acids; extremely durable but should be stored away from harder gemstones like sapphire to avoid scratches
Rarity & Value
Common to Uncommon; value is dictated by translucency, uniformity of color, and lack of black chromite inclusions; high-grade BC or Siberian jade fetches premium prices
Special Characteristics
Highly valued for its structural 'tenacity' which allows for extremely intricate carving without shattering; exhibits a signature greasy feel when polished
Lore & History
Historically revered in China as the 'Stone of Heaven' (Yu) symbolizing purity and moral integrity; used by Maori tribes for 'Mere' weapons and 'Hei-tiki' pendants; traditionally associated with heart chakra and longevity.