Rock Identifier

Category

Metamorphic (Low Grade)

Browse metamorphic (low grade) specimens identified by the Rock Identifier community.

Learn about Metamorphic (Low Grade) in the encyclopedia

Greenschist

Greenschist

Slate

Slate

Granulite

Granulite

Greenstone

Greenstone

Chlorite Schist

Chlorite Schist

Gneiss

Gneiss

Schist

Schist

Amphibolite

Amphibolite

Garnet Schist

Garnet Schist

Migmatite

Migmatite

Biotite Schist

Biotite Schist

Khondalite

Khondalite

Diamond (Uncut/Rough) (Carbon (C)) — mineral

Diamond (Uncut/Rough)

Carbon (C)

Coal (Bituminous) (Bituminous Coal (C)) — sedimentary

Coal (Bituminous)

Bituminous Coal (C)

Gossan (Iron Hat) with Quartz and Chlorite (Limonite/Goethite-rich Gossan (FeO(OH)·nH2O) with inclusions of Quartz and Chlorite) — Mineral/Metamorphic Substrate

Gossan (Iron Hat) with Quartz and Chlorite

Limonite/Goethite-rich Gossan (FeO(OH)·nH2O) with inclusions of Quartz and Chlorite

Mineral/Metamorphic Substrate

Anthracite Coal (Anthracite) — sedimentary

Anthracite Coal

Anthracite

Hardpan Nodule / Ferruginous Sandstone (Ferruginous Sandstone (Fe-cemented sediment)) — sedimentary

Hardpan Nodule / Ferruginous Sandstone

Ferruginous Sandstone (Fe-cemented sediment)

Ironstone concretion (Siderite or Limonite concretion (FeCO3 or FeO(OH)·nH2O)) — sedimentary

Ironstone concretion

Siderite or Limonite concretion (FeCO3 or FeO(OH)·nH2O)

Siltstone (Siltstone (primarily composed of microcrystalline Quartz and Feldspar)) — sedimentary

Siltstone

Siltstone (primarily composed of microcrystalline Quartz and Feldspar)

Ironstone Concretion (Siderite or Limonite Concretion (FeCO3 or FeO(OH)·nH2O)) — sedimentary

Ironstone Concretion

Siderite or Limonite Concretion (FeCO3 or FeO(OH)·nH2O)

Ferruginous Sandstone (Sandstone (arenite) with Limonite/Goethite cement) — sedimentary

Ferruginous Sandstone

Sandstone (arenite) with Limonite/Goethite cement

Conglomerate (Conglomerate (clastic sedimentary rock)) — sedimentary

Conglomerate

Conglomerate (clastic sedimentary rock)

Ironstone (Limonitic Concretion) (Limonite (FeO(OH)·nH2O) with Goethite and Hematite inclusions) — sedimentary

Ironstone (Limonitic Concretion)

Limonite (FeO(OH)·nH2O) with Goethite and Hematite inclusions

Siltstone River Rock (Siltstone (composed of silt-sized particles, silicate minerals)) — sedimentary

Siltstone River Rock

Siltstone (composed of silt-sized particles, silicate minerals)

Limonite Concretion (FeO(OH)·nH2O (Hydrated Iron Oxide)) — sedimentary

Limonite Concretion

FeO(OH)·nH2O (Hydrated Iron Oxide)

Hematitic Sandstone (Sandstone with Hematite inclusions (SiO2 + Fe2O3)) — sedimentary

Hematitic Sandstone

Sandstone with Hematite inclusions (SiO2 + Fe2O3)

Ferruginous Sandstone (River Pebble) (Clastic Sedimentary Rock (Iron-rich)) — sedimentary

Ferruginous Sandstone (River Pebble)

Clastic Sedimentary Rock (Iron-rich)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Limonite (Yellow Ochre) (Hydrated iron(III) oxide-hydroxides (FeO(OH)·nH2O)) — mineral

Limonite (Yellow Ochre)

Hydrated iron(III) oxide-hydroxides (FeO(OH)·nH2O)

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

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Ironstone Pebble (Ferruginous sedimentary rock (Fe2O3 / FeO(OH) mixed with SiO2)) — sedimentary

Ironstone Pebble

Ferruginous sedimentary rock (Fe2O3 / FeO(OH) mixed with SiO2)

Ironstone (likely siderite or goethite-rich siltstone) (Ferruginous Siltstone) — sedimentary

Ironstone (likely siderite or goethite-rich siltstone)

Ferruginous Siltstone

Yellow Ochre / Limonite (Hydrated ferric oxide (FeO(OH)·nH2O)) — mineral

Yellow Ochre / Limonite

Hydrated ferric oxide (FeO(OH)·nH2O)

Schist (Mica Schist (primarily Muscovite or Biotite sheet silicates)) — metamorphic

Schist

Mica Schist (primarily Muscovite or Biotite sheet silicates)

White Jade (Nephrite) (Nephrite, Ca2(Mg,Fe)5Si8O22(OH)2) — Mineral

White Jade (Nephrite)

Nephrite, Ca2(Mg,Fe)5Si8O22(OH)2

Chert (with Epidote/Quartz veining) (Cryptocrystalline silica (SiO2) with Epidote/Quartz inclusions) — sedimentary

Chert (with Epidote/Quartz veining)

Cryptocrystalline silica (SiO2) with Epidote/Quartz inclusions

Glauconitic Sandstone (Glauconitic Quartz Arenite) — sedimentary

Glauconitic Sandstone

Glauconitic Quartz Arenite

Slate (Slate (a fine-grained, foliated metamorphic rock). Mineral composition: Primarily composed of mica minerals (muscovite, chlorite, sericite) and quartz, with minor amounts of hematite, pyrite, and other accessory minerals.) — sedimentary

Slate

Slate (a fine-grained, foliated metamorphic rock). Mineral composition: Primarily composed of mica minerals (muscovite, chlorite, sericite) and quartz, with minor amounts of hematite, pyrite, and other accessory minerals.

Heliotrope (Bloodstone) (Cryptocrystalline Quartz (SiO2) with inclusions of Hematite (Fe2O3)) — mineral

Heliotrope (Bloodstone)

Cryptocrystalline Quartz (SiO2) with inclusions of Hematite (Fe2O3)

Crinoid Marble (Crinoidal Limestone/Marble) — fossil

Crinoid Marble

Crinoidal Limestone/Marble

Epidote in Basalt (Epidotized Basalt (Ca2(Al2,Fe)(SiO4)(Si2O7)O(OH) in Mafic Igneous Host)) — igneous

Epidote in Basalt

Epidotized Basalt (Ca2(Al2,Fe)(SiO4)(Si2O7)O(OH) in Mafic Igneous Host)

Granitoid (with Epidote and Orthoclase) (Crystalline Felsic Intrusive Rock (containing SiO2, KAlSi3O8, and Ca2(Al2,Fe)(Si2O7)(SiO4)O(OH))) — igneous

Granitoid (with Epidote and Orthoclase)

Crystalline Felsic Intrusive Rock (containing SiO2, KAlSi3O8, and Ca2(Al2,Fe)(Si2O7)(SiO4)O(OH))

Anthracite Coal (Anthracite) — sedimentary

Anthracite Coal

Anthracite

White Opal (Hydrated Silica (SiO2·nH2O)) — mineral

White Opal

Hydrated Silica (SiO2·nH2O)

Biotite on Quartz (Biotite (K(Mg,Fe)3AlSi3O10(F,OH)2) and Quartz (SiO2)) — mineral

Biotite on Quartz

Biotite (K(Mg,Fe)3AlSi3O10(F,OH)2) and Quartz (SiO2)

Sulfur (Native Sulfur (S8)) — mineral

Sulfur

Native Sulfur (S8)

Almandine Garnet in Schist (Almandine Garnet (Fe3Al2(SiO4)3) in Mica Schist) — metamorphic

Almandine Garnet in Schist

Almandine Garnet (Fe3Al2(SiO4)3) in Mica Schist

Red Siltstone (Siltstone (primarily quartz and feldspar sized 0.0039 to 0.0625 mm)) — sedimentary

Red Siltstone

Siltstone (primarily quartz and feldspar sized 0.0039 to 0.0625 mm)

Black Sapphire (Corundum (Al2O3)) — mineral

Black Sapphire

Corundum (Al2O3)

Zoisite with Ruby (Anyolite) (Zoisite – Ca2Al3(SiO4)3(OH) with inclusions of Ruby (Al2O3:Cr)) — metamorphic

Zoisite with Ruby (Anyolite)

Zoisite – Ca2Al3(SiO4)3(OH) with inclusions of Ruby (Al2O3:Cr)

Lapis Lazuli (Low-grade/Calcite-heavy) (Na8[Al6Si6O24]n(S,Cl,SO4,OH)2 (Lazurite component)) — metamorphic

Lapis Lazuli (Low-grade/Calcite-heavy)

Na8[Al6Si6O24]n(S,Cl,SO4,OH)2 (Lazurite component)

Celadonite in Amygdaloidal Basalt (K(Mg,Fe2+)(Fe3+,Al)Si4O10(OH)2 (Celadonite mineral) within a Basalt matrix) — igneous

Celadonite in Amygdaloidal Basalt

K(Mg,Fe2+)(Fe3+,Al)Si4O10(OH)2 (Celadonite mineral) within a Basalt matrix

Conglomerate (Conglomerate) — sedimentary

Conglomerate

Conglomerate

Limonite (Limonitic Sandstone) (Hydrated Iron(III) Oxide-Hydroxide ($FeO(OH)·nH_2O$)) — sedimentary

Limonite (Limonitic Sandstone)

Hydrated Iron(III) Oxide-Hydroxide ($FeO(OH)·nH_2O$)