igneous
Blue obsidian (likely carved volcanic glass)
Obsidian, naturally occurring silica-rich volcanic glass (composition commonly rhyolitic)
AI-generated identification · may be incorrectDark blue-black, glossy vitreous luster, no visible crystals or cleavage; hardness about 5–5.5 Mohs. The smooth, shaped surfaces suggest it has been carved or polished.
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Physical properties
Dark blue-black, glossy vitreous luster, no visible crystals or cleavage; hardness about 5–5.5 Mohs. The smooth, shaped surfaces suggest it has been carved or polished.
Formation & geological history
Forms when silica-rich lava cools so rapidly that crystals cannot grow; it is generally Quaternary or younger in exposed volcanic deposits. The image alone cannot establish the specimen’s exact material or age.
Uses & applications
Used for carvings, ornaments, jewelry, and historically for sharp-edged tools; this appears to be a small decorative carving.
Geological facts
Obsidian breaks with a conchoidal fracture and can form exceptionally sharp edges. Blue coloration may be subtle, lighting-dependent, or produced by inclusions or treatment.
Field identification & locations
Check for glassy shine, curved fracture surfaces, and absence of grains; natural obsidian occurs near volcanic areas, including Mexico, the western United States, Iceland, and Japan. A photo cannot confirm whether this is obsidian rather than another dark stone or glass.
