Igneous rocks are rocks that form from the cooling and hardening of magma or lava. Magma is hot, molten rock that is found underground. Lava is magma that has erupted from a volcano and cooled on the surface of the Earth.
There are three main types of igneous rocks:
Igneous rocks are important because they make up much of the Earth's crust. They are also important for the formation of other rocks, such as sedimentary and metamorphic rocks.
Igneous rocks are an important part of the Earth's crust.
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There is no other form of the word "igneous rock". It is a noun that refers to a type of rock that formed from the cooling and solidification of molten rock (magma or lava).
The word "igneous" comes from the Latin word "igneus", which means "fiery" or "of fire". This is a very accurate description of igneous rocks, as they are formed from molten rock that is very hot.
What is igneous rock?