Mirrors, jewelry, and knives were made from _____________________.
Obsidian
Volcanic rock
Diamonds
Sapphires


Sagot :

Answer:

-Obsidian

Explanation:

-Obsidian is hard, brittle, and amorphous; it therefore fractures with sharp edges. In the past, it was used to manufacture cutting and piercing tools, and it has been used experimentally as surgical scalpel blades