Apache tears
Encyclopedia
Apache tears are rounded nodules
Nodule (geology)
A nodule in petrology or mineralogy is a secondary structure, generally spherical or irregularly rounded in shape. Nodules are typically solid replacement bodies of chert or iron oxides formed during diagenesis of a sedimentary rock...

 of obsidian
Obsidian
Obsidian is a naturally occurring volcanic glass formed as an extrusive igneous rock.It is produced when felsic lava extruded from a volcano cools rapidly with minimum crystal growth...

 (volcanic black glass) with diameter from about 0.5 to 5 cm. An Apache tear looks opaque
Opacity (optics)
Opacity is the measure of impenetrability to electromagnetic or other kinds of radiation, especially visible light. In radiative transfer, it describes the absorption and scattering of radiation in a medium, such as a plasma, dielectric, shielding material, glass, etc...

 by reflected light, but translucent when held up to light. Apache tears are usually black, but can range from black to red to brown. They are often found embedded in a greyish-white perlite
Perlite
Perlite is an amorphous volcanic glass that has a relatively high water content, typically formed by the hydration of obsidian. It occurs naturally and has the unusual property of greatly expanding when heated sufficiently...

 matrix.

The name "Apache tear" comes from a legend of the Apache
Apache
Apache is the collective term for several culturally related groups of Native Americans in the United States originally from the Southwest United States. These indigenous peoples of North America speak a Southern Athabaskan language, which is related linguistically to the languages of Athabaskan...

 tribe: about 75 Apaches and the US Cavalry fought on a mountain overlooking what is now Superior, Arizona in the 1870s. Facing defeat, the outnumbered Apache warriors rode their horses off the mountain to their deaths rather than be killed. The wives and families of the warriors cried when they heard of the tragedy; their tears turned into stone upon hitting the ground.

American singer songwriter Johnny Cash
Johnny Cash
John R. "Johnny" Cash was an American singer-songwriter, actor, and author, who has been called one of the most influential musicians of the 20th century...

 wrote lyrics entitled Apache Tears for his album Bitter Tears (Ballads Of The American Indian).

On the Mohs scale, Apache tears fall between 5 and 5.5.
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