Angelite
Anhydrite (Calcium Sulfate) · Semi-Precious Gemstone / Mineral Specimen
Crystal System
Orthorhombic; typically massive, granular, or in the case of tumbled stones, rounded and smooth
Mineral Group
Sulfates (Anhydrous Sulfate)
Chemical Formula
CaSO4
Formation Process
Sedimentary/Evaporite; forms when gypsum (CaSO4·2H2O) loses its water of hydration through heat or pressure, often in sedimentary basins
About This Crystal
A soft, pastel blue to lilac-blue stone with a waxy to vitreous luster. This tumbled specimen is opaque with subtle white mottling and a smooth, even surface
Physical Characteristics
Color: Pale blue to sky blue; Streak: White; Cleavage: Perfect in three directions; Fracture: Uneven/Splintery; Specific Gravity: 2.9–3.0; Fluorescence: None to weak violet
Optical Properties
Biaxial positive; Refractive Index: 1.57–1.61; Birefringence: 0.044; Non-pleochroic; Singly/Doubly refractive: Doubly refractive
Hardness & Durability
Origin Region
Primarily Peru (near Pasco); also found in Mexico, Germany, and Great Britain
Hardness & Durability
Mohs Hardness: 3.5; Very soft and fragile; prone to scratching and cleavage fractures. Not recommended for high-wear jewelry
Care & Maintenance
Extremely sensitive to water; will hydrate back into gypsum (becoming white and chalky). Clean only with a soft dry cloth; avoid ultrasonic cleaners and chemicals
Rarity & Value
Relatively common; affordable for collectors. Value depends on color saturation and smoothness of polish; usually untreated but sometimes dyed
Special Characteristics
Porous nature makes it susceptible to moisture absorption; notable for its specific pale blue 'Glacier Blue' hue caused by trace minerals
Lore & History
Discovered in Peru in 1987. Traditionally associated with the Throat, Third Eye, and Crown chakras; believed to foster peace, communication, and angelic connection