Snowflake Obsidian

Click images to zoom
£5.00

Obsidian is a naturally occurring volcanic glass formed as an extrusive igneous rock. It is produced when felsic lava extruded from a volcano cools without crystal growth.

Physical properties of Snowflake Obsidian:

Chemical composition: 70–75% SiO2, plus MgO, Fe3O4

 

Hardness: 5 - 5.5

 

Specific gravity: 2.6

Weight: 12 g
Dimensions: 3.5 cm × 2.5 cm × 1 cm
£5.00