Title: List of rock types Content: __NOTOC__ ==List== Sorted by name; initial letter means Igneous, Sedimentary or Metamorphic rocks. === A === :I Andesite – an intermediate volcanic rock :M Anthracite – a form of hard coal === B === :S Banded iron formation – a fine grained chemical sedimentary rock composed of iron oxide minerals :S Bauxite – the main ore of aluminium. It is mostly aluminium oxide. :I Basalt – grey/black fine-grained rock from lava which cooled on the surface of the Earth. :S Blue Lias – a formation of rocks, part of the Jurassic Coast World Heritage Site. :S Breccia – a sedimentary or tectonic rock composed of fragments of other, broken rocks === C === :S Chalk – a fine grained carbonate rock composed mainly of coccoliths :S Chert – a fine grained chemical sedimentary rock composed of silica :S Clastic rock – composed of fragments, or clasts, of pre-existing rock. :S Claystone – a sedimentary rock formed from clay :S Coal – a sedimentary rock formed from peat :S Concretion – a concretion is a rock in which a mineral cement fills the spaces between the sediment grains. :S Conglomerate – a sedimentary rock composed of large rounded fragments of other rocks :S Coquina – a sedimentary carbonate rock formed by accumulation of abundant shell fossils and fragments === D === :I Dacite – a felsic to intermediate volcanic rock with high iron content :S Diatomite – a sedimentary rock fromed from diatom fossils :I Diorite – a coarse grained intermediate plutonic rock :S Dolomite – a carbonate rock composed of calcium magnesium carbonate: CaMg(CO3)2 :I Dunite – a rock made mostly of olivine === E === :Evaporite – a chemical sedimentary rock formed by accumulation of minerals after evaporation === F === :S Flint – a form of chert :I Foidolite – a plutonic igneous rock composed of >90% feldspathoid minerals === G === :I Gabbro – a coarse grained plutonic rock chemically equivalent to basalt. Plutonic = magma cooled below surface of the Earth. :M : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : :I Granite – a coarse grained plutonic rock composed of orthoclase, plagioclase and quartz :M Granulite – a high grade metamorphic rock formed from basalt; also a facies of metamorphic rocks :M Greenschist – a generic term for a mafic metamorphic rock dominated by green amphiboles :S Greenstone – greenish sandstone; and a geologic formation in Great Britain :S Greywacke – an immature sandstone with quartz, feldspar and rock fragments within a clay matrix :S Gritstone – a coarse sandstone formed from small pebbles === H === :I Horneblendite – a mafic or ultramafic cumulate rock dominated by >90% hornblende :M Hornfels – a metamorphic rock formed by heating by an igneous rock === I === :I Ignimbrite – a fragmental volcanic rock === K === :I Kimberlite – a rare ultramafic, ultrapotassic volcanic rock and a source of diamonds === L === :S Lignite – brown coal :S Limestone – a sedimentary rock composed primarily of carbonate minerals === M === :M Marble – a metamorphosed limestone :S Marl (geology) – a limestone with a considerable proportion of silicate material :M Migmatite – a high grade metamorphic rock verging upon melting into a magma :S Mudrock – a sedimentary rock composed of clay and muds :S Mudstone – a type of mudrock === N === :I Nephelinite – a silica undersaturated plutonic rock with >90% nepheline === O === :I Obsidian – volcanic glass :S Woolite – a chemical sedimentary limestone (formed by precipitation) === P === :I Pegmatite – an igneous rock (or metamorphic rock) with giant sized crystals :I Peridotite – a plutonic or cumulate ultramafic rock composed of >90% olivine :M Phyllite – a low grade metamorphic rock composed mostly of micaceous minerals :I Plutonic rocks – intrusive rocks that crystallized from magma slowly cooling below the surface of the Earth. :I Pumice – a fine grained volcanic rock with gas bubbles inside :I Pyroclastic rocks – rocks of volcanic origin === Q === :M Quartzite – a metamorphosed sandstone typically composed of >95% quartz === R === :I Rhyolite – a felsic volcanic === S === :S Sandstone – a clastic sedimentary rock defined by its grain size :M Schist – a low to medium grade metamorphic rock :M Serpentinite – a metamorphosed ultramafic rock dominated by serpentine minerals :S Shale – a clastic sedimentary rock defined by its grain size :S Siltstone – a clastic sedimentary rock defined by its grain size :M Skarn – calcium-bearing silicate rocks of any age: a metasomatic rock :M Slate – a low grade metamorphic rock formed from shale or silts :M Steatite – Steatite or soapstone is a metamorphic rock. It has a large amount of the mineral talc. :I Syenite – a plutonic rock dominated by orthoclase feldspar; a type of granitoivolcanic rock; can be a generic term ===T=== :I Tonalite – a plagioclase-dominant granitoid :S Travertine – a carbonate precipitate from hot-springs. :S Tufa – a porous carbonate precipitate from ambient-temperature water :I Tuff – a fine grained volcanic rock formed from volcanic ash === V === :I Variolite === W === :S Dickstone – a matrix-supported carbonate sedimentary rock ==Related pages== *List of minerals *Igneous rock *Sedimentary rock *Metamorphic rock *Geology Types Category:Science-related lists