Metamorphic means “change of form” in Greek.Metamorphic rocks were all once other kinds of rocks. They were CHANGED to become metamorphic rocks.
Metamorphic rocks are made by heat and pressure. When rocks are close to the mantle (by the hot magma) they are changed. When rocks are pushed down below other rocks (plate movement) then the pressure also changes rock into metamorphic.
Metamorphic rocks are also made when plate are pushed together. The pressure from two huge tectonic plates can change rocks into metamorphic.
Minerals in Metamorphic Rocks Rocks are made of minerals. Minerals in metamorphic rocks become tightly packed and large. (can CHANGE minerals into different minerals) Minerals only found in metamorphic rocks: Chlorite Garnet Staurolite kyanite
Identifying Metamorphic RocksRock Color Foliated Grain SizeSlate Dark gray Yes fineSchist Mixture No MediumGneiss Pink/gray Yes coarseMarble Light No CoarseQuartzite Light Not coarse
Using Metamorphic RocksMetamorphic rocks are used for many different things.Marble is commonly used for buildings and sculptures.Slate is used to make tiles for roofs.