Snowflake Obsidian
Obsidian var. Snowflake Obsidian · Decorative Stone / Mineral Specimen
Crystal System
Amorphous (Non-crystalline volcanic glass)
Mineral Group
Mineraloid
Chemical Formula
SiO2 with varying amounts of H2O, Fe, and Mg; the white snowflake patterns are composed of cristobalite inclusions
Formation Process
Extrusive igneous process occurring when silica-rich lava cools rapidly without sufficient time for crystal growth, followed by partial devitrification over time which forms the radial clusters of cristobalite
About This Crystal
An opaque, dark black volcanic glass featuring distinct, contrasting white or grey radial snowflake-like crystal patterns (cristobalite) scattered across its surface, displaying a smooth, vitreous to sub-vitreous luster
Physical Characteristics
Black and white body color with a white streak, amorphous habit with no cleavage, breaks with a characteristically sharp conchoidal fracture, specific gravity around 2.35 to 2.45, and is brittle with a glass-like tenacity
Optical Properties
Isotropic (singly refractive as an amorphous glass), refractive index is approximately 1.48 to 1.51, and it exhibits no pleochroism or major optical phenomena other than the patterned inclusions
Hardness & Durability
Origin Region
Found globally where felsic lava cools rapidly, with notable deposits in the USA (Utah, Oregon, Arizona), Mexico, Iceland, and Italy
Hardness & Durability
Mohs hardness of 5 to 5.5, moderate toughness but can be chipped easily due to its brittle nature and sharp conchoidal fracture; suitable for protected jewelry settings or ornamental carvings
Care & Maintenance
Clean with warm soapy water and a soft cloth, avoid ultrasonic cleaners, harsh chemicals, and extreme thermal shock; store separately to prevent scratching softer stones and being scratched by harder stones
Rarity & Value
Common and widely accessible; value is determined by the clarity of the snowflake patterns and the contrast against the black glass matrix, making most specimens quite affordable
Special Characteristics
Features distinct radial clusters of white cristobalite crystals embedded within a dark volcanic glass matrix, creating a snowflake-like visual pattern
Lore & History
Historically used by ancient civilizations for cutting tools, arrowheads, and mirrors. In modern metaphysical practices, it is regarded as a stone of purity, balance, and grounding, traditionally associated with the root chakra