Obsidian (noun)

A type of naturally occurring volcanic glass that is black in color and often used for making tools and jewelry.

Origin:

The word 'obsidian' comes from the name of the roman obsidius, who was believed to have discovered the stone.

Examples:

1. The obsidian arrowhead was found by the archeologists in the ancient ruins.
2. The obsidian knife was used for hunting and food preparation.
3. Obsidian is a type of volcanic glass that forms from the rapid cooling of lava.
4. The obsidian pendant was a treasured item in the jewelry collection.
5. The obsidian rock formations in the national park are a popular tourist attraction.