igneous
Snowflake Obsidian
Volcanic Glass with Spherulite inclusions (SiO2)
Hardness: 5-5.5 (Mohs); Color: Black with white or gray patches; Luster: Vitreous/Glassy; Structure: Amorphous (non-crystalline) with crystalline inclusions; Cleavage: None (Conchoidal fracture)
- Hardness
- 5-5
- Color
- Black with white or gray patches
- Luster
- Vitreous/Glassy
Identified More igneous →
Explore Snowflake Obsidian in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 5-5.5 (Mohs); Color: Black with white or gray patches; Luster: Vitreous/Glassy; Structure: Amorphous (non-crystalline) with crystalline inclusions; Cleavage: None (Conchoidal fracture)
Formation & geological history
Formed when felsic lava cools rapidly with minimal crystal growth. The 'snowflakes' are spherulites, which are radial clusters of cristobalite crystals formed through devitrification of the glass.
Uses & applications
Used primarily in jewelry, lapidary arts (beads, cabochons), ornamental carvings, and stone healing practices.
Geological facts
Unlike regular obsidian, snowflake obsidian has undergone a process where the glass begins to turn back into solid crystal over millions of years. It was historically used for making sharp tools and arrowheads.
Field identification & locations
Identify by its characteristic white flowery patterns on a pitch-black glassy base. Commonly found in volcanic regions such as the American West (Utah, Oregon), Mexico, and Iceland.
