Obsidian

An igneous rock, black or very dark volcanic GLASS, shattered into very sharp blades and sometimes used as a tool for working marble on a small scale. It has also been employed since ancient times as an ornament in sculpture, in particular for the pupils of inserted eyes.
Show lessRead more
© Grove Art / OUP

Discover this medium

166 items

Interested in Science?

Get updates with your personalized Culture Weekly

You are all set!

Your first Culture Weekly will arrive this week.

Google apps