igneous
Obsidian (Apache Tear)
Volcanic Glass (Amorphous Silicon Dioxide, SiO2)
Hardness: 5-5.5 on Mohs scale; Color: Black to smoky translucent; Luster: Vitreous/Glassy; Structure: Amorphous (non-crystalline); Cleavage: None (conchoidal fracture); Specific Gravity: 2.35-2.6
- Hardness
- 5-5
- Color
- Black to smoky translucent
- Luster
- Vitreous/Glassy
Identified More igneous →
Explore Obsidian (Apache Tear) in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 5-5.5 on Mohs scale; Color: Black to smoky translucent; Luster: Vitreous/Glassy; Structure: Amorphous (non-crystalline); Cleavage: None (conchoidal fracture); Specific Gravity: 2.35-2.6
Formation & geological history
Formed from the rapid cooling of silica-rich rhyolitic lava. 'Apache Tears' are specifically rounded sub-types found within perlite matrices. They range from Tertiary to Quaternary in geological age.
Uses & applications
Used in jewelry (cabochons), as metaphysical 'healing' stones, and historically for surgical-grade sharp blades. Highly popular among rockhound collectors.
Geological facts
Legend says they were formed from the tears of family members mourning Apache warriors who leaped to their deaths from a cliff to avoid capture by cavalry. They are technically a liquid that cooled so fast it never crystallized.
Field identification & locations
Identify in the field by their smooth, rounded shape and translucency when held up to a bright light. Commonly found in Arizona, Nevada, and New Mexico (USA) often embedded in grey, crumbly perlite.
