Igneous

Snowflake Obsidian

Vitreous volcanic silicate (SiO2 with Cristobalite inclusions)

Hardness: 5-5.5 (Mohs scale); Color: Black with white or gray flower-like patterns; Luster: Vitreous/Glassy; Structure: Amorphous (non-crystalline glass); Cleavage: None (Conchoidal fracture); Specific Gravity: 2.3 - 2.6.

Hardness: 5-5
Color: Black with white or gray flower-like patterns
Luster: Vitreous/Glassy

Identified March 26, 2026More igneous →

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Physical properties

Formation & geological history

Formed when felsic lava cools rapidly with minimal crystal growth. The 'snowflakes' are inclusions of the mineral Cristobalite, which form through a process of devitrification. Most specimens are relatively young geologically (Cenozoic era).

Uses & applications

Primarily used in jewelry (cabochons and beads), ornamental carvings, and as a popular semi-precious stone for mineral collectors and metaphysical practices.

Geological facts

Despite having 'crystals' within it (the flakes), the base material is actually a natural volcanic glass. Ancient cultures often used obsidian for surgical blades because it can be fractured to an edge many times sharper than a steel scalpel.

Field identification & locations

Identify by its distinctive white 'snowflake' patches against a jet-black glassy background. It is commonly found in areas of recent volcanic activity such as Iceland, Mexico, and the Western United States (Utah and Oregon). It lacks the sharp transparency of pure obsidian.

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