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A complete list of the rocks

Igneous Rocks:

  • Adakite – A class of intermediate to felsic volcanic rocks containing low amounts of yttrium and ytterbium
  • Andesite – An intermediate volcanic rock
  • Alkali feldspar granite – A granitoid in which at least 90% of the total feldspar is alkali feldspar
  • Anorthosite – A mafic intrusive igneous rock composed predominantly of plagioclase
  • Aplite – A fine-grained intrusive igneous rock type similar to granite
  • Basalt – A magnesium- and iron-rich extrusive igneous rock
    • A’a – Basaltic lava with a crumpled appearance
    • Pahoehoe – Basaltic lava with a flowing, often ropy appearance
  • Basaltic trachyandesite
    • Mugearite – Oligoclase-bearing basalt, comprising olivine, apatite, and opaque oxides
    • Shoshonite – A potassium-rich variety of basaltic trachyandesite
  • Basanite – A silica-undersaturated basalt
  • Blairmorite – Rare porphyritic volcanic rock
  • Boninite – Ultramafic extrusive rock high in both magnesium and silica
  • Carbonatite – Igneous rock with more than 50% carbonate minerals
  • Charnockite – A type of granite containing orthopyroxene
    • Enderbite – An igneous rock of the charnockite series
  • Dacite – Volcanic rock intermediate in composition between andesite and rhyolite
  • Diabase, also known as dolerite – An intrusive mafic rock forming dykes or sills
  • Diorite – Intermediate intrusive igneous rock composed principally of plagioclase feldspar
    • Napoleonite, also known as corsite – A variety of diorite with orbicular structure
  • Dunite – An ultramafic and ultrabasic rock from Earth’s mantle and made of the mineral olivine.
  • Essexite – a dark gray or black holocrystalline plutonic rock
  • Foidolite – A rare coarse-grained intrusive igneous rock in which more than 60% of light-coloured minerals are feldspathoids
  • Gabbro – A coarse-grained mafic intrusive rock
  • Granite – common type of intrusive, felsic, igneous rock with granular structure
  • Granodiorite – A phaneritic-textured intrusive igneous rock similar to granite
  • Granophyre – A subvolcanic rock that contains quartz and alkali feldspar in characteristic angular intergrowths
  • Harzburgite – An ultramafic and ultrabasic mantle rock. Found in ophiolites.
  • Hornblendite – Plutonic rock consisting mainly of the amphibole hornblende
  • Hyaloclastite – A volcaniclastic accumulation or breccia
  • Icelandite – An iron rich, aluminium poor andesite
  • Ignimbrite – A variety of hardened tuff
  • Ijolite – An igneous rock consisting essentially of nepheline and augite
  • Kimberlite – Igneous rock which sometimes contains diamonds
  • Komatiite – An ultramafic mantle-derived volcanic rock
  • Lamproite – Ultrapotassic mantle-derived volcanic or subvolcanic rock
  • Lamprophyre – An ultramafic, ultrapotassic intrusive rock dominated by mafic phenocrysts in a feldspar groundmass
  • Latite – A silica-undersaturated form of andesite
  • Lherzolite – An ultramafic rock, essentially a peridotite
  • Monzogranite – A silica-undersaturated granite with <5% normative quartz
  • Monzonite – Igneous intrusive rock with low quartz and equal plagioclase and alkali feldspar – a plutonic rock with <5% normative quartz
  • Nepheline syenite – A silica-undersaturated plutonic rock of nepheline and alkali feldspar
  • Nephelinite – A silica-undersaturated plutonic rock with >90% nepheline
  • Norite – A hypersthene-bearing gabbro
  • Obsidian – Naturally occurring volcanic glass
  • Pegmatite – Igneous rock with very large interlocked crystals
  • Peridotite – A coarse-grained ultramafic igneous rock
  • Phonolite – A silica-undersaturated volcanic rock; essentially similar to nepheline syenite
  • Phonotephrite – A volcanic rock with a composition between phonolite and tephrite
  • Picrite – An olivine-bearing basalt
  • Porphyry – Textural form of igneous rock with large grained crystals in a fine matrix
  • Pumice – Light coloured highly vesicular volcanic rock
  • Pyroxenite – Igneous rock – a coarse grained plutonic rock composed of >90% pyroxene
  • Quartz diorite – A diorite with >5% modal quartz
  • Quartz monzonite – An intermediate plutonic rock, essentially a monzonite with 5–10% modal quartz
  • Quartzolite – An intrusive rock composed mostly of quartz
  • Rhyodacite – A felsic volcanic rock which is intermediate between a rhyolite and a dacite
  • Rhyolite – An igneous, volcanic rock, of felsic (silica-rich) composition
    • Comendite – A hard, peralkaline igneous rock, a type of light blue grey rhyolite
    • Pantellerite – A peralkaline rhyolite type of volcanic rock
  • Scoria – Dark vesicular volcanic rock
  • Shonkinite – Intrusive igneous rock – a plutonic rock
  • Sovite – A coarse-grained carbonatite rock
  • Syenite – Intrusive igneous rock – A plutonic rock dominated by orthoclase feldspar; a type of granitoid
  • Tachylyte – Essentially a basaltic glass
  • Tephriphonolite – A volcanic rock with a composition between phonotephrite and phonolite
  • Tephrite – A silica-undersaturated volcanic rock
  • Tonalite – A plagioclase-dominant granitoid
  • Trachyandesite – An alkaline intermediate volcanic rock
    • Benmoreite – A silica-undersaturated volcanic rock of intermediate composition – sodic trachyandesite
  • Trachybasalt – A volcanic rock with a composition between basalt and trachyte
    • Hawaiite – a sodic type of trachybasalt, typically formed by ocean island (hot spot) volcanism
  • Trachyte – A silica-undersaturated volcanic rock; essentially a feldspathoid-bearing rhyolite
  • Troctolite – Igneous rock – A plutonic ultramafic rock containing olivine, pyroxene and plagioclase
  • Trondhjemite – A light-colored intrusive igneous rock – A form of tonalite where plagioclase-group feldspar is oligoclase
  • Tuff – Rock consolidated from volcanic ash
  • Websterite – A type of pyroxenite, composed of clinoproxene and orthopyroxene
  • Wehrlite – Ultramafic rock – An ultramafic plutonic or cumulate rock, a type of peridotite, composed of olivine and clinopyroxene

Sedimentary Rocks:

  • Argillite – Sedimentary rock, mostly of indurated clay particles
  • Arkose – A type of sandstone containing at least 25% feldspar
  • Banded iron formation – Distinctive layered units of iron-rich sedimentary rock that are almost always of Precambrian age
  • Breccia – Rock composed of broken fragments cemented by a matrix
  • Calcarenite – A type of limestone that is composed predominantly of sand-size grains
  • Chalk – A soft, white, porous sedimentary rock made of calcium carbonate
  • Chert – A hard, fine-grained sedimentary rock composed of cryptocrystalline silica
  • Claystone – Clastic sedimentary rock composed primarily of clay-sized particles
  • Coal – Combustible sedimentary rock composed primarily of carbon
  • Conglomerate – A coarse-grained clastic sedimentary rock with mainly rounded to subangular clasts
  • Coquina – A sedimentary rock that is composed mostly of fragments of shells
  • Diamictite – A lithified sedimentary rock of non- to poorly sorted terrigenous sediment in a matrix of mudstone or sandstone
  • Diatomite – Soft, siliceous sedimentary rock that is easily crumbled
  • Dolomite (rock), also known as Dolostone – Sedimentary carbonate rock that contains a high percentage of the mineral dolomite
  • Evaporite – A water-soluble mineral deposit formed by evaporation from an aqueous solution
  • Flint – Cryptocrystalline form of the mineral quartz
  • Geyserite – A form of opaline silica that is often found around hot springs and geysers
  • Greywacke – A hard, dark sandstone with poorly sorted angular grains in a compact, clay-fine matrix
  • Gritstone – A hard, coarse-grained, siliceous sandstone
  • Itacolumite – A porous, yellow sandstone that is flexible when cut into thin strips
  • Jaspillite – A banded mixture of hematite and quartz
  • Laterite – A product of rock weathering in wet tropical climate rich in iron and aluminum
  • Lignite – soft, brown, combustible, sedimentary rock
  • Limestone – Sedimentary rocks made of calcium carbonate
  • Marl – Lime-rich mud or mudstone which contains variable amounts of clays and silt
  • Mudstone – Fine grained sedimentary rock whose original constituents were clays or muds
  • Oil shale – Organic-rich fine-grained sedimentary rock containing kerogen
  • Oolite – Sedimentary rock formed from ooids
  • Phosphorite – A non-detrital sedimentary rock that contains high amounts of phosphate minerals
  • Sandstone – Type of sedimentary rock
  • Shale – A fine-grained, clastic sedimentary rock
  • Siltstone – Sedimentary rock which has a grain size in the silt range
  • Sylvinite – A sedimentary rock made of a mechanical mixture of sylvite and halite
  • Tillite – Till which has been indurated or lithified by burial
  • Travertine – A form of limestone deposited by mineral springs
  • Tufa – Porous limestone rock formed when carbonate minerals precipitate out of ambient temperature water
  • Turbidite – The geologic deposit of a turbidity current
  • Wackestone – A mud-supported carbonate rock that contains greater than 10% grains

Metamorphic Rocks:

  • Anthracite – A hard, compact variety of coal that has a submetallic luster
  • Amphibolite – A metamorphic rock containing mainly amphibole and plagioclase
  • Blueschist – A metavolcanic rock that forms by the metamorphism of basalt and rocks with similar composition
  • Cataclasite – A rock formed by faulting
  • Eclogite – A dense metamorphic rock formed under high pressure
  • Gneiss – A common high-grade metamorphic rock
  • Granulite – A class of high-grade medium to coarse grained metamorphic rocks
  • Greenschist – A mafic metamorphic rock dominated by green amphiboles
  • Hornfels
    • Calcflinta – A type of hornfels found in the Scottish Highlands
  • Litchfieldite – Nepheline syenite gneiss
  • Marble – Non-foliated, metamorphic rock, commonly used for sculpture and as a building material – a metamorphosed limestone
  • Migmatite – A mixture of metamorphic rock and igneous rock
  • Mylonite – A metamorphic rock formed by shearing
  • Metapelite – A metamorphic rock with a protolith of clay-rich (siltstone) sedimentary rock
  • Metapsammite – A metamorphic rock with a protolith of quartz-rich (sandstone) sedimentary rock
  • Phyllite – A low grade metamorphic rock composed mostly of micaceous minerals
  • Pseudotachylite – A glass formed by melting within a fault via friction
  • Quartzite – Hard, non-foliated metamorphic rock which was originally pure quartz sandstone – A metamorphosed sandstone typically composed of >95% quartz
  • Schist – Medium grade metamorphic rock with lamellar grain
  • Serpentinite – Rock formed by hydration and metamorphic transformation of olivine
  • Skarn – Hard, coarse-grained, hydrothermally altered metamorphic rocks
  • Slate – Metamorphic rock – A low grade metamorphic rock formed from shale or silts
  • Suevite – Rock consisting partly of melted material formed during an impact event – A rock formed by partial melting during a meteorite impact
  • Talc carbonate – A metamorphosed ultramafic rock with talc as an essential constituent; similar to a serpentinite
    • Soapstone – Essentially a talc schist
  • Tectonite – A rock whose fabric reflects the history of its deformation
  • Whiteschist – A high pressure metamorphic rock containing talc and kyanite

Specific Varieties of the rocks:

The following are terms for rocks that are not petrographically or genetically distinct but are defined according to various other criteria; most are specific classes of other rocks, or altered versions of existing rocks. Some archaic and vernacular terms for rocks are also included.

  • Adamellite – A variety of quartz monzonite
  • Appinite – A group of varieties of lamprophyre, mostly rich in hornblende
  • Aphanite – Igneous rocks which are so fine-grained that their component mineral crystals are not detectable by the unaided eye
  • Borolanite – A variety of nepheline syenite from Loch Borralan, Scotland
  • Blue Granite – An igneous rock, specifically a variety of monzonite
  • Epidosite – A hydrothermally altered epidote- and quartz-bearing rock
  • Felsite – A very fine grained felsic volcanic rock that may or may not contain larger crystals
  • Flint – Cryptocrystalline form of the mineral quartz
  • Ganister – Hard, fine-grained quartzose sandstone, or orthoquartzite
  • Gossan – Intensely oxidized, weathered or decomposed rock
  • Hyaloclastite – A volcaniclastic accumulation or breccia
  • Ijolite – An igneous rock consisting essentially of nepheline and augite
  • Jadeitite – A metamorphic rock found in blueschist-grade metamorphic terranes
  • Jasperoid – A hematite-silica metasomatite analogous to a skarn
  • Kenyte – A variety of porphyritic phonolite or trachyte with rhomb shaped phenocrysts of anorthoclase with variable olivine and augite in a glassy matrix – A variety of phonolite, first found on Mount Kenya
  • Lapis lazuli – Contact metamorphic rock containing lazurite, pyrite and calcite – A rock composed of lazurite and other minerals
  • Larvikite – An igneous rock, specifically a variety of monzonite
  • Litchfieldite – A metamorphosed nepheline syenite occurrence near Litchfield, Maine
  • Llanite – A hypabyssal rhyolite with microcline and blue quartz phenocrysts from the Llano Uplift in Texas
  • Luxullianite – A rare type of granite
  • Mangerite – A plutonic intrusive igneous rock, that is essentially a hypersthene-bearing monzonite
  • Minette – A variety of lamprophyre
  • Novaculite – A type of chert found in Oklahoma, Arkansas, and Texas
  • Pietersite – Breccia rock of hawk’s eyes and tiger’s eyes
  • Pyrolite – A chemical analogue considered to theoretically represent the earth’s upper mantle
  • Rapakivi granite – A hornblende-biotite granite containing large round crystals of orthoclase each with a rim of oligoclase
  • Rhomb porphyry – A type of latite with euhedral rhombic phenocrysts of feldspar
  • Rodingite – A mafic rock metasomatized by serpentinization fluids
  • Shonkinite – Intrusive igneous rock – melitilic and kalsititic rocks
  • Taconite – Iron-bearing sedimentary rock, in which the iron minerals are interlayered with quartz, chert, or carbonate
  • Tachylite – A form of basaltic volcanic glass
  • Teschenite – A silica undersaturated, analcime bearing gabbro
  • Theralite – A nepheline gabbro
  • Unakite – An altered granite
  • Variolite – Igneous rocks which contain varioles
  • Vogesite – A variety of lamprophyre
  • Wad – A rock rich in manganese oxide or manganese hydroxide