gemstone
Blue Obsidian
Volcanic Glass (Silica, SiO2)
AI-generated identification · may be incorrectMohs hardness 5 to 5.5, vibrant blue color often due to treatment or specific inclusions, vitreous luster, amorphous crystal structure, conchoidal fracture.
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Physical properties
Mohs hardness 5 to 5.5, vibrant blue color often due to treatment or specific inclusions, vitreous luster, amorphous crystal structure, conchoidal fracture.
Formation & geological history
Formed from rapidly cooling felsic lava where crystal growth is inhibited, often enhanced or artificially colored for the gemstone market.
Uses & applications
Widely used for ornamental carvings, polished tumbles, metaphysical practices, and jewelry making.
Geological facts
Natural blue obsidian is exceedingly rare; most commercial specimens are either man-made glass or artificially colored natural clear obsidian.
Field identification & locations
Easily identified by its glassy luster and smooth conchoidal fracture, found globally where volcanic activity occurred.
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