Nephrite Jade
Nephrite (Tremolite-Actinolite series) · Semi-Precious Gemstone / Ornamental Stone
Crystal System
Monoclinic; typically occurs in massive, microcrystalline, or fibrous felted aggregates rather than distinct crystals.
Mineral Group
Silicates (Inosilicates; Amphibole Group)
Chemical Formula
Ca2(Mg,Fe)5Si8O22(OH)2
Formation Process
Metamorphic; typically formed through contact metamorphism of magnesium-rich limestones (dolomites) or the metasomatism of ultramafic rocks.
About This Crystal
Deep spinach-green to olive-green beads with a greasy to vitreous luster. These specimens appear translucent to opaque with a dense, tough texture characteristic of interlocking fibrous structures.
Physical Characteristics
Color: Dark green with possible black inclusions of chromite or magnetite; Streak: White; Fracture: Splintery to uneven; Specific Gravity: 2.90–3.03; Fluorescence: Typically inert.
Optical Properties
Refractive Index: ~1.606–1.632; Birefringence: 0.023 to 0.027 (usually not visible in massive forms); Optical Character: Biaxial negative.
Hardness & Durability
Origin Region
British Columbia (Canada), Xinjiang (China), New Zealand, Russia, and Wyoming (USA).
Hardness & Durability
Mohs Hardness: 6.0–6.5; Toughness: Exceptional (due to felted structure, it is one of the toughest natural stones); Stability: Excellent.
Care & Maintenance
Clean with warm soapy water and a soft brush; avoid harsh chemicals and acids. Store separately to prevent softer stones from being scratched by it, though it is highly resistant to breaking.
Rarity & Value
Common to Uncommon; value is driven by color uniformity, translucency, and lack of dark inclusions. Intense 'spinach green' is highly valued.
Special Characteristics
Known for its extreme toughness. High-quality nephrite may show a degree of chatoyancy if fibrous, but it is most noted for its waxy/greasy feel when polished.
Lore & History
Historically known as the 'Stone of Heaven' in China, used for over 5,000 years in ritual objects and weaponry. Traditionally associated with longevity, heart chakra healing, and protection.