Obsidian 4mm Faceted Round Natural Gemstone Strand

1x 4mm Faceted Obsidian Gemstone Strand

Strand Length 38cm

Hole Size approx 0.8mm

Hand Faceted.

This sale is for one strand

Obsidian is a naturally occurring volcanic glass formed when lava extruded from a volcano cools rapidly with minimal crystal growth. It is an igneous rock. Obsidian is produced from felsic lava, rich in the lighter elements such as silicon, oxygen, aluminium, sodium, and potassium. It is commonly found within the margins of rhyolitic lava flows known as obsidian flows. These flows have a high content of silica, granting them a high viscosity. The high viscosity inhibits diffusion of atoms through the lava, which inhibits the first step in the formation of mineral crystals. Together with rapid cooling, this results in a natural glass forming from the lava.