Here's why:

* Metamorphic comes from the Greek words "meta" (change) and "morph" (form).

* Metamorphic rocks are formed when existing rocks (igneous, sedimentary, or even other metamorphic rocks) are subjected to intense heat and pressure deep within the Earth's crust. This process changes the rock's mineral composition, texture, and sometimes even its chemical makeup.

Examples of metamorphic rocks:

* Marble: Formed from limestone

* Slate: Formed from shale

* Gneiss: Formed from granite

* Quartzite: Formed from sandstone