Examples of Various Rock Types

Seite 1

Granite

Igneous rock

Contains large crystals

Hard rock

Cooled slowly under the surface of the Earth (intrustive)

Composed mainly of quartz

Found mainly in Dartmoor, southern Devon, England.

Seite 2

Basalt

Igneous rock

Contains non-visible crystals

Hard rock

Cooled quickly on the surface of the earth (extrusive)

Composed mainly of plagioclase and pyroxene minerals

Found mainly in northern Co. Antrim, most famously at the Giant's Causeway

Seite 3

Chalk

Sedimentary rock

Composed of calcium carbonate

Porous

Susceptible to weathering by solution

Primarily found in the South Downs

Seite 4

Sandstone

Sedimentary rock

Composed of compressed layers of sand

Hard rock

Commonly used for paving

Found at Baggy Point, Devon

Seite 5

Schist

Metamorphic Rock

Usually forms on a continental side of a convergent plate boundary where sedimentary rocks have been subjected to pressure and heat.

Formed mainly from shale

Contain visible crystals

Can be found in South Devon

Seite 6

Slate

Metamorphic rock

Composed of shale

Extremely fine-grained

Typically used in building

Commonly found in Snowdonia