igneous
Obsidian (Carved)
Volcanic glass (high-silica amorphous glass, >70% SiO2)
AI-generated identification · may be incorrectHardness 5-5.5 on Mohs scale; jet black, vitreous luster, conchoidal fracture, amorphous structure with specific gravity around 2.4.
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Physical properties
Hardness 5-5.5 on Mohs scale; jet black, vitreous luster, conchoidal fracture, amorphous structure with specific gravity around 2.4.
Formation & geological history
Formed by the extremely rapid cooling of felsic, silica-rich lava which inhibits crystal lattice growth, typically in volcanic zones.
Uses & applications
Carved into decorative talismans, statues, ornamental carvings, jewelry beads, and historic cutting tools or scalpels.
Geological facts
Obsidian was extensively prized by Mesoamerican cultures for blades sharper than modern surgical steel, and is commonly carved into decorative mythological creatures today.
Field identification & locations
Recognized by its glassy texture, shell-like fracture surfaces, smooth tactile feel, and deep black opaque to translucent body.
