igneous
Snowflake Obsidian (possibly mixed with Jasper or other matrix)
Obsidian with Cristobalite inclusions
AI-generated identification · may be incorrectHardness 5-5.5. Typically black or dark brown background with white 'snowflake' patches (spherulites of cristobalite). Luster is vitreous (glassy) to dull. Amorphous structure (glass). Conchoidal fracture.
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Physical properties
Hardness 5-5.5. Typically black or dark brown background with white 'snowflake' patches (spherulites of cristobalite). Luster is vitreous (glassy) to dull. Amorphous structure (glass). Conchoidal fracture.
Formation & geological history
Formed from rapidly cooling felsic lava without crystal growth, typically in volcanic environments. The 'snowflakes' are formed by the devitrification (crystallization) of the glass over time, producing cristobalite.
Uses & applications
Commonly used in jewelry (cabochons, beads), carving, and lapidary work. Highly valued by collectors for its unique pattern.
Geological facts
Historically used for making sharp tools like arrowheads and blades due to its conchoidal fracture. The 'snowflakes' are actually a form of high-temperature quartz called cristobalite.
Field identification & locations
Identify by its glassy texture, conchoidal fracture, and distinctive white snowflake patterns on a dark background. Often found in areas with recent volcanic activity.
