igneous
Obsidian
Volcanic Glass
AI-generated identification · may be incorrectHardness of 5 to 5.5 on the Mohs scale, deep black color, vitreous luster, amorphous crystal structure with distinct conchoidal fracture.
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Physical properties
Hardness of 5 to 5.5 on the Mohs scale, deep black color, vitreous luster, amorphous crystal structure with distinct conchoidal fracture.
Formation & geological history
Formed as extrusive igneous rock when felsic lava cools rapidly with minimal crystal growth.
Uses & applications
Used historically for cutting tools and arrowheads, and currently in ornamental jewelry and metaphysical collections.
Geological facts
Despite appearing as a mineral, obsidian is actually a mineraloid because its rapid cooling prevents true crystal formation.
Field identification & locations
Easily identified by its extremely sharp edges, glassy texture, and conchoidal fracture patterns found near volcanic regions.
