Here's how it works:
* Existing rocks (igneous, sedimentary, or even other metamorphic rocks) are subjected to intense heat and pressure deep within the Earth's crust.
* The heat causes the minerals in the rock to recrystallize and change their structure.
* The pressure can cause the rocks to fold, deform, and become more compact.
* This process of transformation results in a new rock with a different texture, mineral composition, and often a different appearance than the original rock.
Examples of metamorphic rocks formed through heating and cooling include:
* Marble: Formed from limestone.
* Slate: Formed from shale.
* Gneiss: Formed from granite.
* Quartzite: Formed from sandstone.
