Obsidian       Type of Rock: IGNEOUS - Extrusive igneous Rock

  • dark, black
  • smooth surface
  • glassy luster, vireous
  • called "nature's glass"
  • breaks with a sharp conchoidal fracture
  • formed during slow cooling of lava

Obsidian Varieties

  • there are many varieties named after the appearance of obsidian
  • the variety is caused by the chemical mixture of the magma when it cooled, its chemical composition
Black Obsidian                Snowflake Obsidian              Mahogany Obsidian

Snowflake Obsidian   USA


Mahogany Obsidian   Glass Butte, Oregon  USA

This is an obsidian chunk that has been tumbled about. Notice the dull, gray exterior and the roundness of the piece. Where the rock is freshly broken, the colour is bright and the surface looks shiny, glass-like.

Mahogany Obsidian carved sculpture of a Rhino

Apache Tears

Apache tears are tear drop shaped pieces of obsidian.
Mahogany Obsidian Egg from between Tequila & Ameca, Estado De Jalisco, MEXICO
Mahogany Obsidian from Mount Lassen, California  USA
Tiger Obsidian from Mount Lassen, California  USA
Banded Obsidian from Glass Buttes, Oregon  USA
Rainbow Obsidian from Glass Buttes, Oregon  USA


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