igneous
Obsidian (Apache Tear)
Amorphous Volcanic Glass (SiO2)
Hardness: 5.0 to 5.5 on Mohs scale; Color: Black, smoky grey, or deep brown; Luster: Vitreous (glassy); Crystal Structure: Amorphous (non-crystalline); Fracture: Conchoidal; Transparency: Partially translucent when held to light.
- Hardness
- 5
- Color
- Black, smoky grey, or deep brown
- Luster
- Vitreous (glassy)
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Physical properties
Hardness: 5.0 to 5.5 on Mohs scale; Color: Black, smoky grey, or deep brown; Luster: Vitreous (glassy); Crystal Structure: Amorphous (non-crystalline); Fracture: Conchoidal; Transparency: Partially translucent when held to light.
Formation & geological history
Formed through the rapid cooling of silica-rich (rhyolitic) lava. These specifically occur within perlite beds where small nodules of glass remain after most of the surrounding material hydrates and turns into perlite.
Uses & applications
A popular specimen for rock hounds and collectors; used in jewelry like necklaces and rings; often used in metaphysical practices for grounding and protection.
Geological facts
Legend has it that the tears of Apache women, mourning for warriors who jumped from a cliff to avoid capture, turned into these stones when they hit the ground. Scientifically, they are hydrated obsidian nodules.
Field identification & locations
Identify in the field by looking for rounded, black glassy pebbles within greyish, crumbly perlite deposits. Hold them up to a strong light source; they should be translucent or smoky rather than opaque.
