Rock Identifier

Category

Metamorphic Or Igneous (Context Dependent)

Browse metamorphic or igneous (context dependent) specimens identified by the Rock Identifier community.

Kyanite in Quartz (Al2SiO5 in SiO2) — metamorphic

Kyanite in Quartz

Al2SiO5 in SiO2

Anthracite Coal (Anthracite) — sedimentary

Anthracite Coal

Anthracite

Quartzite with Gneissic Banding (Quartzite (primarily SiO2) with mafic mineral inclusions) — metamorphic

Quartzite with Gneissic Banding

Quartzite (primarily SiO2) with mafic mineral inclusions

Schist (Mica Schist) — metamorphic

Schist

Mica Schist

Blue Quartz (Aventurine) (Silicon Dioxide (SiO2) with fibrous inclusions (commonly Dumortierite)) — mineral

Blue Quartz (Aventurine)

Silicon Dioxide (SiO2) with fibrous inclusions (commonly Dumortierite)

Almandine Garnet in Matrix (Almandine, Fe3Al2(SiO4)3) — metamorphic

Almandine Garnet in Matrix

Almandine, Fe3Al2(SiO4)3

Quartzite (Quartzite (primarily SiO2)) — metamorphic

Quartzite

Quartzite (primarily SiO2)

Schist (Mica Schist (Medium-grade metamorphic rock)) — metamorphic

Schist

Mica Schist (Medium-grade metamorphic rock)

Biotite Schist (Biotite Mica Schist [K(Mg,Fe)3AlSi3O10(OH,F)2]) — metamorphic

Biotite Schist

Biotite Mica Schist [K(Mg,Fe)3AlSi3O10(OH,F)2]

Pyrite (Iron Sulfide (FeS2)) — mineral

Pyrite

Iron Sulfide (FeS2)

Quartzite pebble (Quartzite (primarily SiO2)) — metamorphic

Quartzite pebble

Quartzite (primarily SiO2)

Quartzite with Iron Inclusions (Metamorphosed Quartz Sandstone (SiO2 with Fe2O3)) — metamorphic

Quartzite with Iron Inclusions

Metamorphosed Quartz Sandstone (SiO2 with Fe2O3)

Quartzite (Iron-stained) (Quartzite (SiO2 with iron oxides)) — metamorphic

Quartzite (Iron-stained)

Quartzite (SiO2 with iron oxides)

Rough Emerald (Emerald (Beryl), Be3Al2(SiO3)6) — mineral

Rough Emerald

Emerald (Beryl), Be3Al2(SiO3)6

Phyllite (Phyllite) — metamorphic

Phyllite

Phyllite

Quartzite River Rock (Quartzite (primarily SiO2)) — metamorphic

Quartzite River Rock

Quartzite (primarily SiO2)

Schist (Mica Schist (Composition typically involves Muscovite, Biotite, Quartz, and Feldspar)) — metamorphic

Schist

Mica Schist (Composition typically involves Muscovite, Biotite, Quartz, and Feldspar)

Schist (Kyanite Schist) (Kyanite-Mica Schist (primarily Al2SiO5, KAl2(AlSi3O10)(OH)2, and SiO2)) — metamorphic

Schist (Kyanite Schist)

Kyanite-Mica Schist (primarily Al2SiO5, KAl2(AlSi3O10)(OH)2, and SiO2)

Rough Emerald (Beryl) (Emerald (Be3Al2(SiO3)6 with Cr/V impurities)) — mineral

Rough Emerald (Beryl)

Emerald (Be3Al2(SiO3)6 with Cr/V impurities)

Milky Quartz with Mica inclusions (Quartz (Silicon Dioxide, SiO2)) — mineral

Milky Quartz with Mica inclusions

Quartz (Silicon Dioxide, SiO2)

Jadeite (Jade) (NaAlSi2O6 (Sodium Aluminum Silicate)) — metamorphic

Jadeite (Jade)

NaAlSi2O6 (Sodium Aluminum Silicate)

Serpentine (Antigorite/Lizardite (Mg,Fe)3Si2O5(OH)4) — metamorphic

Serpentine

Antigorite/Lizardite (Mg,Fe)3Si2O5(OH)4

Alexandrite (Chrysoberyl (BeAl2O4 with Chromium impurities)) — mineral

Alexandrite

Chrysoberyl (BeAl2O4 with Chromium impurities)

Beryl (Aquamarine) in Matrix with Schorl (Be3Al2Si6O18 (Beryl) with NaFe3Al6(BO3)3Si6O18(OH)4 (Schorl)) — mineral

Beryl (Aquamarine) in Matrix with Schorl

Be3Al2Si6O18 (Beryl) with NaFe3Al6(BO3)3Si6O18(OH)4 (Schorl)

Aquamarine (Beryl (Be₃Al₂Si‑₆O₁₈)) — mineral

Aquamarine

Beryl (Be₃Al₂Si‑₆O₁₈)

Grey Agate (Tumbled) (Silicon Dioxide (SiO2)) — mineral

Grey Agate (Tumbled)

Silicon Dioxide (SiO2)

Aquamarine (Beryl (Be3Al2Si6O18 with iron impurities)) — mineral

Aquamarine

Beryl (Be3Al2Si6O18 with iron impurities)

Green Adventurine (SiO2 (Silicon Dioxide with inclusions of Fuchsite mica)) — mineral

Green Adventurine

SiO2 (Silicon Dioxide with inclusions of Fuchsite mica)

Grey Slate (Foliated Metamorphic Rock (formed by low-grade regional metamorphism of shale or mudstone)) — metamorphic

Grey Slate

Foliated Metamorphic Rock (formed by low-grade regional metamorphism of shale or mudstone)

Fuchsite (Chromium-rich Muscovite (K(Al,Cr)2(AlSi3O10)(OH)2)) — mineral

Fuchsite

Chromium-rich Muscovite (K(Al,Cr)2(AlSi3O10)(OH)2)

Yellow Calcite (Calcium Carbonate (CaCO3)) — mineral

Yellow Calcite

Calcium Carbonate (CaCO3)

Dumortierite Quartz (Dumortierite (Al7BCuO15)) — metamorphic

Dumortierite Quartz

Dumortierite (Al7BCuO15)

Jadeite Jade (NaAlSi2O6 (Sodium Aluminum Silicate)) — metamorphic

Jadeite Jade

NaAlSi2O6 (Sodium Aluminum Silicate)

Quartzite (Metamorphic Rock (Mainly SiO2)) — metamorphic

Quartzite

Metamorphic Rock (Mainly SiO2)

Galena (Lead(II) sulfide (PbS)) — mineral

Galena

Lead(II) sulfide (PbS)

Jadeite and Mixed Gemstones (Ruby, Sapphire, Emerald) (Jadeite (NaAlSi2O6), Corundum (Al2O3), Beryl (Be3Al2(Si6O18))) — mineral

Jadeite and Mixed Gemstones (Ruby, Sapphire, Emerald)

Jadeite (NaAlSi2O6), Corundum (Al2O3), Beryl (Be3Al2(Si6O18))

Mica Schist (Foliated Metamorphic Rock (Schist)) — metamorphic

Mica Schist

Foliated Metamorphic Rock (Schist)

Mica Schist (Mica Schist (primarily Muscovite and Biotite KAl2(AlSi3O10)(OH)2)) — metamorphic

Mica Schist

Mica Schist (primarily Muscovite and Biotite KAl2(AlSi3O10)(OH)2)

Garnet (likely Almandine) (Almandine - Fe3Al2(SiO4)3) — mineral

Garnet (likely Almandine)

Almandine - Fe3Al2(SiO4)3

Schist (Graphite or Mica rich) (Crystalline Schist (often containing Muscovite, Biotite, or Graphite)) — metamorphic

Schist (Graphite or Mica rich)

Crystalline Schist (often containing Muscovite, Biotite, or Graphite)

Marble (Marble (metamorphosed limestone or dolostone), primarily composed of calcite (CaCO3) or dolomite (CaMg(CO3)2)) — metamorphic

Marble

Marble (metamorphosed limestone or dolostone), primarily composed of calcite (CaCO3) or dolomite (CaMg(CO3)2)

Schist (Mica Schist) — metamorphic

Schist

Mica Schist