TYPES OF ROCKS

IGNEOUS-2 most common are granite & basalt:

GRANITE:-formed when molten magma is forced into the crust cools very slowly(large crystals) eventually comes to the surface after rock wears away colour-black,grey or pink used for monuments found in mourne &wicklow mountains

BASALT:formedwhen lava spreads along earths surface cools quickely(tiny crystals invisible to naked eye) colou-dark grey to black antrim/derry plateau(giants causeway-lava shrunk and craked into hexagonal columns)

SEDIMENTARY:2 common  types=limestone&sandstone

LIMESTONE:formed on beds of shallow warm seas made of skeletons of tiny sea creatures,fish&shells(millions of years) they compress and cement together colour-white/grey permeable(water can pass through) found in burren co.clare and central /midland of ireland most common stone in ireland used to make monuments/cement farmers use it to improve soil fertility

SANDSTONE:formed when large amounts of sand are transported by wind/rivers deposited on beds of lakes/rivers/deserts layers built up and compress and cement together(form sandstone) colour-brown/red used as a building material munster mainly

METAMORPHIC:eg.marble&quartzite

MARBLE:used to be limestone before molten magma put heat + pressure on it colour-pure marble-white      when other minerals present-red/green/blck contains crystals fireplaces gravestones and ornaments(easily cut and polished) rathin island(white) connemara(green) cork(red)

QUARTZITE:formed when sandstone comes into contact with magma deep in earths crust happens during periods of folding consists mainly of grains of quartzite packed closely together colour-grey/white caps of mountains(croagh patrick,great sugerloaf)

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