Approx 5cm each 
Gorgeous raw lumps of snowflake obsidian 
Snowflake Obsidian is formed when the felsic lava from a volcano rapidly cools down with very minimum crystal growth. It's basically a volcanic glass that formed as an igneous rock. Snowflake Obsidian is usually black in color, with white patches called Phenocryst. It resembles snowflakes, hence the name.