Which type of rock is formed through cooling and solidification of magma?

The formation of igneous rock occurs through the cooling and solidification of magma, which is molten rock found beneath the Earth's surface. When magma rises and reaches the Earth's surface, it can erupt as lava, or it can cool and solidify underground. This solidification process results in the formation of igneous rocks, characterized by their crystalline texture and mineral composition.

Igneous rocks can be classified into two main types based on their formation location: intrusive (or plutonic) igneous rocks form when magma cools slowly beneath the surface, resulting in larger crystals, while extrusive (or volcanic) igneous rocks form when lava cools rapidly at the surface, leading to smaller crystals. The properties of igneous rocks make them distinct from sedimentary rocks, which form from the compaction of sediments, and metamorphic rocks, which arise from the transformation of existing rocks due to heat, pressure, or chemically active fluids. Clay rock is not a recognized category in geological terms, typically referring to a type of sediment or material rather than a specific rock classification.

Understanding the process of formation of igneous rocks provides insight into geological processes and the rock cycle, which is fundamental in the study of Earth sciences.