Rock Identifier

Category

Metamorphic Or Igneous Alteration

Browse metamorphic or igneous alteration specimens identified by the Rock Identifier community.

Learn about Metamorphic Or Igneous Alteration in the encyclopedia

Cordierite Hornfels

Cordierite Hornfels

Migmatite

Talc-carbonate Rock

Talc-carbonate Rock

Hornblende Schist

Hornblende Schist

Epidosite

Oregon Opal

Orendite

Orthoclase

Orca Agate

Orange Opal

Peacock Ore

Orange Garnet

Milk Quartz (White) and Yellow Aventurine (Yellow) (Silicon Dioxide (SiO2)) — mineral

Milk Quartz (White) and Yellow Aventurine (Yellow)

Silicon Dioxide (SiO2)

Pyrite (Iron Sulfide (FeS2)) — mineral

Pyrite

Iron Sulfide (FeS2)

Hematite (Ferric Oxide (Fe2O3)) — mineral

Hematite

Ferric Oxide (Fe2O3)

Hematite (Iron(III) oxide (Fe2O3)) — mineral

Hematite

Iron(III) oxide (Fe2O3)

Sapphire (Corundum (Al2O3)) — mineral

Sapphire

Corundum (Al2O3)

Green Aventurine (Quartz with Fuchsite inclusions (SiO2)) — mineral

Green Aventurine

Quartz with Fuchsite inclusions (SiO2)

Tumbled Ruby (Corundum (Al2O3:Cr)) — gemstone

Tumbled Ruby

Corundum (Al2O3:Cr)

Serpentine (Antigorite, Lizardite, or Chrysotile; (Mg,Fe)3Si2O5(OH)4) — metamorphic

Serpentine

Antigorite, Lizardite, or Chrysotile; (Mg,Fe)3Si2O5(OH)4

Epidote in Quartz (Epidote (Ca2(Al,Fe)3(SiO4)3(OH)) in Milky Quartz (SiO2)) — metamorphic

Epidote in Quartz

Epidote (Ca2(Al,Fe)3(SiO4)3(OH)) in Milky Quartz (SiO2)

Tumbled epidote-bearing granite or amphibolite (Quartz–feldspar rock with dark amphibole/biotite and epidote; exact identification is uncertain from the image) — igneous

Tumbled epidote-bearing granite or amphibolite

Quartz–feldspar rock with dark amphibole/biotite and epidote; exact identification is uncertain from the image

Greenstone (Metabasalt / Greenschist) — metamorphic

Greenstone

Metabasalt / Greenschist

Greenstone / Epidosite (Epidosite (Metasomatic rock consisting mainly of Epidite Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH) and Quartz)) — metamorphic

Greenstone / Epidosite

Epidosite (Metasomatic rock consisting mainly of Epidite Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH) and Quartz)

Unakite (Unakite (Epidotized Granite)) — metamorphic

Unakite

Unakite (Epidotized Granite)

Weathered granite or granitic gneiss (Granite; chiefly quartz, feldspar, and mica, possibly with gneissic foliation) — igneous

Weathered granite or granitic gneiss

Granite; chiefly quartz, feldspar, and mica, possibly with gneissic foliation

Aquamarine (Beryl) Beads (Beryllium aluminum silicate (Be3Al2Si6O18)) — gemstone

Aquamarine (Beryl) Beads

Beryllium aluminum silicate (Be3Al2Si6O18)

Serpentine Pebble (Serpentine ((Mg,Fe,Ni,Al,Zn,Mn)3(Si,Al)2O5(OH)4)) — metamorphic

Serpentine Pebble

Serpentine ((Mg,Fe,Ni,Al,Zn,Mn)3(Si,Al)2O5(OH)4)

Greenstone / Epidosite (Epidosite (primary minerals: Epidote and Quartz)) — metamorphic

Greenstone / Epidosite

Epidosite (primary minerals: Epidote and Quartz)

Yellow Aventurine (specifically a carved crescent moon) (Silicon Dioxide (SiO2) with inclusions) — mineral

Yellow Aventurine (specifically a carved crescent moon)

Silicon Dioxide (SiO2) with inclusions

Milky Quartz (Crystalline Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Crystalline Silicon Dioxide (SiO2)

Quartz in Matrix (or Quartz Vein Rock) (Silicon Dioxide (SiO2) with host rock) — igneous

Quartz in Matrix (or Quartz Vein Rock)

Silicon Dioxide (SiO2) with host rock

Orange Aventurine / Quartz (Silicon Dioxide (SiO2) with Hematite or Goethite inclusions) — mineral

Orange Aventurine / Quartz

Silicon Dioxide (SiO2) with Hematite or Goethite inclusions

Hematite (Iron(III) oxide (Fe2O3)) — mineral

Hematite

Iron(III) oxide (Fe2O3)

Muscovite (White Mica) (Muscovite - Potassium aluminum silicate: KAl2(AlSi3O10)(F,OH)2) — Mineral

Muscovite (White Mica)

Muscovite - Potassium aluminum silicate: KAl2(AlSi3O10)(F,OH)2

Sapphire (Blue/Violet Rough) (Corundum (Al2O3)) — gemstone

Sapphire (Blue/Violet Rough)

Corundum (Al2O3)

Green Granite / Verd Antique (Serpentinite / Metasomatized Peridotite) — metamorphic

Green Granite / Verd Antique

Serpentinite / Metasomatized Peridotite

Epidosite (Epidosite (predominantly Epidote {Ca2Al2Fe3+Si3O12(OH)} and Quartz {SiO2})) — metamorphic

Epidosite

Epidosite (predominantly Epidote {Ca2Al2Fe3+Si3O12(OH)} and Quartz {SiO2})

Epidosite (Unakite-related) (Epidosite (predominantly Epidote, Ca2(Al2,Fe3+)(SiO4)3(OH))) — metamorphic

Epidosite (Unakite-related)

Epidosite (predominantly Epidote, Ca2(Al2,Fe3+)(SiO4)3(OH))

Serpentinite (Serpentinite (Hydrated magnesium iron silicate)) — metamorphic

Serpentinite

Serpentinite (Hydrated magnesium iron silicate)

Bull Quartz with Mica and Host Rock (Massive Quartz (SiO2) with Muscovite/Chlorite inclusions) — igneous

Bull Quartz with Mica and Host Rock

Massive Quartz (SiO2) with Muscovite/Chlorite inclusions

Quartz Pebble (River Agate / Chalcedony) (Silicon Dioxide (SiO2)) — mineral

Quartz Pebble (River Agate / Chalcedony)

Silicon Dioxide (SiO2)

Blue Sapphire (Corundum (Al2O3)) — mineral

Blue Sapphire

Corundum (Al2O3)

Mica Sand / Vermiculite (Phyllosilicate group (typically Biotite or Muscovite)) — mineral

Mica Sand / Vermiculite

Phyllosilicate group (typically Biotite or Muscovite)

Green Aventurine (Quartz with Fuchsite inclusions (SiO2)) — mineral

Green Aventurine

Quartz with Fuchsite inclusions (SiO2)

Milky Quartz (Quartz (Silicon Dioxide, SiO2)) — mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Green Greenstone / Celadonite-bearing Metamorphic Rock (Greenschist / Celadonite / Serpentinitic pebble) — metamorphic

Green Greenstone / Celadonite-bearing Metamorphic Rock

Greenschist / Celadonite / Serpentinitic pebble

Quartz Vein (Silicon Dioxide (SiO2)) — Mineral

Quartz Vein

Silicon Dioxide (SiO2)

Oyster shell fragment (Ostreidae shell; primarily calcite (CaCO₃)) — fossil

Oyster shell fragment

Ostreidae shell; primarily calcite (CaCO₃)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Epidosite (Epidosite (Metasomatic calcium-aluminum silicate rock)) — metamorphic

Epidosite

Epidosite (Metasomatic calcium-aluminum silicate rock)

Serpentine (Serpentinite (Mg,Fe,Ni,Al,Zn)3Si2O5(OH)4) — metamorphic

Serpentine

Serpentinite (Mg,Fe,Ni,Al,Zn)3Si2O5(OH)4

Polished dark mineral fragments, likely hematite or magnetite (Hematite (Fe₂O₃) or magnetite (Fe₃O₄)) — mineral

Polished dark mineral fragments, likely hematite or magnetite

Hematite (Fe₂O₃) or magnetite (Fe₃O₄)