Snowflake Obsidian Bead Strand Round Various SizesThis listing is for a strand of round snowflake obsidian beads. Available in 4mm, 6mm, 8mm, 10mm. Obsidian is a natural form of volcanic glass. Being a form of glass, Obsidian can break causing sharp edges and was often used for tools and weapons by people long ago. Obsidian is typically black but occasionally two different types of lava flowed together but were so viscous they did not mix completely thus producing different colors as seen in Mahogany