igneous
Snowflake Obsidian
Obsidian with Cristobalite inclusions
Hardness: 5-5.5. Color: Black with white 'snowflake' patches. Luster: Vitreous. Crystal structure: Amorphous (obsidian) with crystalline inclusions (cristobalite). Fracture: Conchoidal. Specific gravity: ~2.4.
- Hardness
- 5-5
- Color
- Black with white 'snowflake' patches
- Luster
- Vitreous
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Physical properties
Hardness: 5-5.5. Color: Black with white 'snowflake' patches. Luster: Vitreous. Crystal structure: Amorphous (obsidian) with crystalline inclusions (cristobalite). Fracture: Conchoidal. Specific gravity: ~2.4.
Formation & geological history
Formed from rapidly cooling felsic lava. The 'snowflakes' are inclusions of the mineral cristobalite, which crystallized as the lava cooled.
Uses & applications
Used in lapidary arts, jewelry making, and carved ornamental objects.
Geological facts
The snowflake patterns are spherulites of the mineral cristobalite.
Field identification & locations
Identified by its distinctive black background with white, radiating patches. Often found in areas with recent volcanic activity.
