Which of following is not an igneous rock.
Pumice
Obsidion
Or limestone
Your answer is?
Here is some information to help you decide- It is super easy:
Pumice igneous rock
Pumice is a highly vesicular pyroclastic igneous rock of intermediate to siliceous magmas including rhyolite, trachyte and phonolite. Pumice is usually light in colour ranging from white, yellowish, gray, gray brown, and a dull red. Pumice has an average porosity of 90%
Obsidian is a naturally occurring volcanic glass formed as an extrusive igneous rock. It is produced when felsic lava extruded from a volcano cools rapidly with minimum crystal growth.
Limestone is a sedimentary rock, composed mainly of skeletal fragments of marine organisms such as coral, forams and molluscs. Its major materials are the minerals calcite and aragonite, which are different crystal forms of calcium carbonate. About 10% of sedimentary rocks are limestones