Snowflake obsidian is a form of volcanic glass that ... It appears as a dark glassy rock that’s typically black, although it can take on hues of green, brown, and other colors due to impurities.

Volcanic eruption buried ancient ... Italy's Mount Vesuvius erupted in 79 AD found dark fragments resembling obsidian inside ...

Obsidian is perhaps best known in its role as the dark black blade atop ancient spears ... including shades of green, purple, and blue. Colorful, sure, but we’d say it reminds us more of an ...