Rock Identifier
Apache Tear (Obsidian) (Volcanic Glass (Amorphous SiO2)) — igneous
igneous

Apache Tear (Obsidian)

Volcanic Glass (Amorphous SiO2)

Hardness of 5 to 5.5 on the Mohs scale, dark black to smoky brown color, vitreous luster, amorphous crystal structure (no cleavage), specific gravity of approximately 2.35 to 2.40.

Identified More igneous
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Physical properties

Hardness of 5 to 5.5 on the Mohs scale, dark black to smoky brown color, vitreous luster, amorphous crystal structure (no cleavage), specific gravity of approximately 2.35 to 2.40.

Formation & geological history

Formed from rapidly cooling felsic lava (silica-rich) that does not have time to grow crystals, typically associated with rhyolitic volcanic flows.

Uses & applications

Used in lapidary arts, jewelry making, ornamental carvings, and as a popular collector specimen.

Geological facts

Legend says that Apache Tears are the petrified tears of grieving women whose warriors fell to their deaths during a clash with US cavalry near Superior, Arizona.

Field identification & locations

Found commonly in the western United States, particularly around Superior, Arizona. In the field, it appears as small, rounded nodules embedded in a grey perlite matrix.