igneous

Snowflake Obsidian

Hydrated Volcanic Glass (primarily SiO2) with Cristobalite inclusions

Hardness: 5-5.5; Color: Black with grayish-white radial patterns; Luster: Vitreous/Glassy; Structure: Amorphous (glass) with spherulitic inclusions; Fracture: Conchoidal

Hardness: 5-5
Color: Black with grayish-white radial patterns
Luster: Vitreous/Glassy

Identified April 9, 2026More igneous →

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Physical properties

Hardness: 5-5.5; Color: Black with grayish-white radial patterns; Luster: Vitreous/Glassy; Structure: Amorphous (glass) with spherulitic inclusions; Fracture: Conchoidal

Formation & geological history

Formed when felsic lava cools rapidly with minimal crystal growth, with 'snowflakes' created through devitrification over time as Cristobalite crystals form in the glass

Uses & applications

Primarily used for decorative purposes, jewelry (cabochons, beads), and in holistic practices as a 'grounding' stone

Geological facts

The white patches are actually radiating clusters of the mineral cristobalite, a high-temperature polymorph of silica. Unlike true crystals, obsidian is a cooled liquid and is technically a mineraloid.

Field identification & locations

Identifiable by its sharp glass-like fracture and distinctive white-on-black floral patterns; commonly found in areas of recent volcanic activity like Utah, USA, and Mexico

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