Snowflake obsidian
Rock
Also called Flower obsidian
About it
Black obsidian with white, flower-like clusters of cristobalite crystals that grew in the glass. Polished for beads, cabochons, and tumbled stones; much of it comes from Utah.
- Type
- Rock (igneous)
- Group
- Igneous (volcanic glass)
- Hardness (Mohs)
- 5–5.5
- Specific gravity
- 2.3–2.6
- Lustre
- vitreous (glassy)
- Colours
- black with white or grey spots
- Transparency
- opaque
- Cleavage and fracture
- none; conchoidal fracture
Typical values: real specimens vary. For more, see mindat.org.