igneous
Snowflake Obsidian
Volcanic Glass with Cristobalite inclusions
Hardness of 5 to 5.5 on the Mohs scale, black base color with white or grey snowflake-like patches (cristobalite), vitreous luster, amorphous crystal structure (volcanic glass), conchoidal fracture, specific gravity around 2.35 to 2.45
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Physical properties
Hardness of 5 to 5.5 on the Mohs scale, black base color with white or grey snowflake-like patches (cristobalite), vitreous luster, amorphous crystal structure (volcanic glass), conchoidal fracture, specific gravity around 2.35 to 2.45
Formation & geological history
Formed from felsic lava that has cooled rapidly with little crystal growth, allowing cristobalite crystals to grow in radial clusters (cristobalite spherulites) as it devitrifies over time
Uses & applications
Used in ornamental objects, polished gemstones, jewelry, and crystal healing collections
Geological facts
The 'snowflakes' are actually clusters of needle-like cristobalite minerals that grew within the volcanic glass during the slow devitrification process
Field identification & locations
Easily identified by its deep black background contrasted with distinctive white snowflake patterns; commonly found in regions with volcanic activity such as the western United States, Mexico, and Iceland
