Nephrite Jade
Nephrite (Tremolite-Actinolite series) · Semi-Precious Gemstone / Ornamental Stone
Crystal System
Monoclinic; commonly occurs in massive, microcrystalline, and fibrous interlocking aggregates.
Mineral Group
Silicates (Inosilicates - Amphibole Group)
Chemical Formula
Ca2(Mg,Fe)5Si8O22(OH)2 (Calcium magnesium iron silicate hydroxide)
Formation Process
Forms through regional metamorphism or metasomatism of magnesium-rich rocks (dolomites) or ultramafic rocks (serpentinites) in the presence of silica-rich hydrothermal fluids.
About This Crystal
This specimen is a carved, crescent-shaped stone displaying a deep moss-green color with a slightly mottled, waxy to vitreous luster. It is translucent to opaque with a dense, fine-grained texture characteristic of felted amphibole fibers.
Physical Characteristics
Color: Olive to dark green; Streak: White; Cleavage: Prismatic (rarely visible in massive form); Fracture: Splintery to uneven; Specific Gravity: 2.90–3.03; Fluorescence: Inert (none).
Optical Properties
Refractive Index: 1.600–1.641; Birefringence: 0.027 (usually not measurable in aggregate form); Pleochroism: Weak; Optical Phenomema: None typically visible in this cut.
Hardness & Durability
Origin Region
Notable sources include British Columbia (Canada), New Zealand (Arahura River), Russia (Siberia), China (Hetian), and Taiwan. Often found in alluvial deposits or as lenses in metamorphic rocks.
Hardness & Durability
Mohs Hardness: 6.0–6.5; Toughness: Exceptional (highest of any natural stone due to interlocking fibrous structure); highly durable for jewelry and carving.
Care & Maintenance
Clean with mild soap and warm water; avoid harsh chemicals and ultra-sonic cleaners. Store separately to prevent scratching softer stones. Very stable under normal light and heat.
Rarity & Value
Common to Uncommon; value is determined by color uniformity, translucency, and the absence of black chromite inclusions. Higher quality 'Mutton Fat' or vibrant greens are more valuable.
Special Characteristics
Extreme toughness due to its 'felted' microscopic structure, which prevents cleavage planes from propagating fractures, making it ideal for intricate carving.
Lore & History
Known as the 'Stone of Heaven' in Ancient China; used for over 5,000 years for ritual objects and weaponry. Traditionally associated with longevity, emotional balance, and the heart chakra.