What kind of igneous rock is obsidian?

Answer 1

Obsidian is an igneous rock. However it differs from other rocks because it contains no minerals. It consists of natural glass, which is not a mineral because it has no crystal structure.

Answers from McDougal Littell, Earth Science book

Answer 2

Obsidian is classified as igneous rock, solidified from molten material.

Answer 3

An obsidian rock is an extrusive igneous rock that forms when a volcano erupts and has no time to crystallize, so it has a glassy texture. Obsidian rocks are generally black in color.

Answer 4

most obsidians have a felsic chemistry. Felsic igneous rocks are light-colored

Answer 5

Obsidian is an extrusive felsic volcanic glass.

Answer 6

Obsidian is a type of volcanic glass that forms from the rapid cooling of lava without crystallization. It is usually black in color and has a shiny, glassy texture.