* Metamorphic rocks are formed when existing rocks (igneous, sedimentary, or even other metamorphic rocks) are transformed by heat and pressure. These conditions cause changes in the rock's mineral composition, texture, and sometimes even chemical composition. Think of it like baking a cake - the ingredients (original rock) are changed by heat and pressure to create a completely new, but delicious, product (metamorphic rock).
* Igneous rocks are formed from the cooling and solidification of molten rock (magma or lava).
* Sedimentary rocks are formed from the accumulation and cementation of sediments, like sand, mud, and shells.
So, while all rocks are made up of minerals, metamorphic rocks are unique in their origin. They are not formed from the cooling of magma or the accumulation of sediments, but rather from the transformation of existing rocks.
