Description
OBSIDIAN SPHERE
This is the polished golden obsidian sphere. Diameter 1.9″ (4.9cm). Weight – 5oz (141 grams). Origin: Mexico.
Some information about obsidian:
Obsidian is a naturally occurring volcanic glass formed as an extrusive igneous rock. It produced when felsic lava extruded from a volcano cools rapidly with minimal crystal growth.
It commonly found within the margins of rhyolitic lava flows known as obsidian flows, where the chemical composition (high silica content) causes a high viscosity, which, upon rapid cooling, results in a natural glass forming from the lava. The inhibition of atomic diffusion through this highly viscous lava explains the lack of crystal growth.
Obsidian is hard, brittle, and amorphous; it therefore fractures with sharp edges. In the past, it used to manufacture cutting and piercing tools, and experimentally as surgical scalpel blades.