That’s because obsidian is pretty unstable as far as rocks go; over time, the silica molecules within it end up rearranging into a more organized fashion, a process known as devitrification.

It’s far more badass, because it started out as silica-rich magma, eventually erupting as a viscous surface lava flow. This molten earth origin is what classes rainbow obsidian as an igneous rock.

Snowflake obsidian is a form of volcanic glass that features white or grayish “snowflake” shapes made of embedded cristobalite. These pretty patterns are not artificially added as a cheap ...