POLISHED SNOWFLAKE OBSIDIAN
Snowflake obsidian is a natural volcanic "glass" that forms when molten rock cools so quickly that that atoms do not have enough time to arrange themselves into crystals. Instead, the molten material solidifies into an amorphous solid called volcanic glass. The "snowflakes" in the obsidian are small, white, radially clustered crystals of cristobalite, a mineral polymorph of silica. The primary sources of snowflake obsidian are in Millard County, Utah and Mexico, though it can be found in locations worldwide.