Black Obsidian 8mm Polished Round Natural Gemstone Bead Strand

8mm Obsidian Gemstone Strand

Natural Colour

Polished finish for a luxe feel.

Strand length 37cm

Quality stones

Hole sizes are 0.8mm for each bead.

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.