Rock Identifier

Category

Mineral Specimen

Browse mineral specimen specimens identified by the Rock Identifier community.

Learn about Mineral Specimen in the encyclopedia

Emerald in Matrix

Emerald in Matrix

Aquamarine Matrix

Aquamarine Matrix

Morganite Crystal

Morganite Crystal

Emerald Crystal

Emerald Crystal

Aquamarine Crystal

Aquamarine Crystal

Mushroom Tourmaline

Mushroom Tourmaline

Glauconite

Hutcheonite

Halite

Sperrylite

Baddeleyite

Anatase

Smoky Quartz (Silicon Dioxide (SiO2)) — mineral

Smoky Quartz

Silicon Dioxide (SiO2)

Pegmatite with muscovite mica (Granitic pegmatite; quartz (SiO₂), feldspar, and muscovite (KAl₂(AlSi₃O₁₀)(OH)₂), locally biotite/tourmaline) — igneous

Pegmatite with muscovite mica

Granitic pegmatite; quartz (SiO₂), feldspar, and muscovite (KAl₂(AlSi₃O₁₀)(OH)₂), locally biotite/tourmaline

Anthracite Coal (Anthracite (Carbon-rich metamorphic coal)) — sedimentary

Anthracite Coal

Anthracite (Carbon-rich metamorphic coal)

Pegmatite with Black Tourmaline (Granitic Pegmatite with Schorl (NaFe2+3Al6(Si6O18)(BO3)3(OH)3OH)) — igneous

Pegmatite with Black Tourmaline

Granitic Pegmatite with Schorl (NaFe2+3Al6(Si6O18)(BO3)3(OH)3OH)

Botryoidal Hematite (Iron Stone Conglomerate) (Hematite (Fe2O3) in sedimentary matrix) — sedimentary

Botryoidal Hematite (Iron Stone Conglomerate)

Hematite (Fe2O3) in sedimentary matrix

Weathered banded iron formation (iron-rich quartzite) (Banded iron formation (BIF), chiefly hematite/magnetite and microcrystalline quartz (SiO₂)) — sedimentary

Weathered banded iron formation (iron-rich quartzite)

Banded iron formation (BIF), chiefly hematite/magnetite and microcrystalline quartz (SiO₂)

Epidote (Epidote (Ca2(Al2,Fe3+)3(SiO4)3(OH))) — metamorphic

Epidote

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

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

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Orange Calcite (Banded Calcite) (Calcium Carbonate (CaCO3)) — mineral

Orange Calcite (Banded Calcite)

Calcium Carbonate (CaCO3)

Smoky Quartz (with Druzy/Polished Edge) (Smoky Quartz (Silicon Dioxide, SiO2)) — mineral

Smoky Quartz (with Druzy/Polished Edge)

Smoky Quartz (Silicon Dioxide, SiO2)

Common Opal in Host Rock (Hydrated Silica (SiO2·nH2O)) — mineraloid

Common Opal in Host Rock

Hydrated Silica (SiO2·nH2O)

Chalcedony on Ironstone (Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3/FeOOH)) — sedimentary

Chalcedony on Ironstone

Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3/FeOOH)

Amethyst crystal cluster (Amethyst, purple quartz (SiO₂) colored mainly by iron impurities and irradiation) — mineral

Amethyst crystal cluster

Amethyst, purple quartz (SiO₂) colored mainly by iron impurities and irradiation

Amethyst (Silicon Dioxide (SiO2) with iron impurities) — mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Quartz with Iron Oxide Inclusions (Silicon Dioxide (SiO2) with Hematite/Limonite coatings) — mineral

Quartz with Iron Oxide Inclusions

Silicon Dioxide (SiO2) with Hematite/Limonite coatings

Quartz (milky quartz), possibly calcite (Quartz: SiO₂; visual identification is uncertain because the specimen is wet and lacks diagnostic crystal faces) — mineral

Quartz (milky quartz), possibly calcite

Quartz: SiO₂; visual identification is uncertain because the specimen is wet and lacks diagnostic crystal faces

Limonite (Ironstone Concretion) (Limonite (FeO(OH)·nH2O)) — sedimentary

Limonite (Ironstone Concretion)

Limonite (FeO(OH)·nH2O)

Milky Quartz with Talc / Serpentine (Silicon Dioxide (SiO2) with Mg3Si4O10(OH)2) — metamorphic

Milky Quartz with Talc / Serpentine

Silicon Dioxide (SiO2) with Mg3Si4O10(OH)2

Pyrite (Iron Sulfide (FeS2)) — mineral

Pyrite

Iron Sulfide (FeS2)

Weathered quartz-rich river cobble, possibly quartzite (Quartzite (mostly microcrystalline SiO₂), tentatively identified) — metamorphic

Weathered quartz-rich river cobble, possibly quartzite

Quartzite (mostly microcrystalline SiO₂), tentatively identified

Chalcedony (Agate/Jasper mix in host rock) (Chalcedony (cryptocrystalline Silicon Dioxide, SiO2)) — mineral

Chalcedony (Agate/Jasper mix in host rock)

Chalcedony (cryptocrystalline Silicon Dioxide, SiO2)

Quartz-rich rock fragment, possibly granite or quartzite (Primarily quartz (SiO₂), with possible feldspar and iron-oxide staining) — igneous or metamorphic

Quartz-rich rock fragment, possibly granite or quartzite

Primarily quartz (SiO₂), with possible feldspar and iron-oxide staining

igneous or metamorphic

Pyrite (Fool's Gold) (Iron Sulfide (FeS2)) — mineral

Pyrite (Fool's Gold)

Iron Sulfide (FeS2)

Smoky Quartz (Silicon Dioxide (SiO2) with aluminum impurities and natural irradiation) — mineral

Smoky Quartz

Silicon Dioxide (SiO2) with aluminum impurities and natural irradiation

Smoky Quartz with Siderite and Pyrite (Silicon Dioxide (SiO2) with Ferrous Carbonate (FeCO3) and Iron Sulfide (FeS2)) — mineral

Smoky Quartz with Siderite and Pyrite

Silicon Dioxide (SiO2) with Ferrous Carbonate (FeCO3) and Iron Sulfide (FeS2)

Dolomite on Prehnite (Saddle-shaped Dolomite) (Dolomite [CaMg(CO3)2] on Prehnite [Ca2Al(AlSi3O10)(OH)2]) — mineral

Dolomite on Prehnite (Saddle-shaped Dolomite)

Dolomite [CaMg(CO3)2] on Prehnite [Ca2Al(AlSi3O10)(OH)2]

Possible tektite or iron-rich slag-like natural specimen (Uncertain; possibly natural glass (tektite) or magnetite-rich rock) — mineral

Possible tektite or iron-rich slag-like natural specimen

Uncertain; possibly natural glass (tektite) or magnetite-rich rock

Pyrite (Iron Pyrite (FeS2)) — mineral

Pyrite

Iron Pyrite (FeS2)

Tumbled ruby or ruby-bearing corundum (Corundum (Al₂O₃), red variety colored mainly by chromium) — gemstone

Tumbled ruby or ruby-bearing corundum

Corundum (Al₂O₃), red variety colored mainly by chromium

Pyrite and Fluorite on Quartz (Matrix Specimen) (Iron Disulfide (FeS2) and Calcium Fluoride (CaF2) with Silicon Dioxide (SiO2)) — mineral

Pyrite and Fluorite on Quartz (Matrix Specimen)

Iron Disulfide (FeS2) and Calcium Fluoride (CaF2) with Silicon Dioxide (SiO2)

Orange Calcite (Calcium Carbonate (CaCO3)) — mineral

Orange Calcite

Calcium Carbonate (CaCO3)

Chalcopyrite on Quartz (Copper Iron Sulfide (CuFeS2)) — mineral

Chalcopyrite on Quartz

Copper Iron Sulfide (CuFeS2)

Pink tourmaline crystal (probable) (Elbaite tourmaline, Na(Li,Al)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄) — mineral

Pink tourmaline crystal (probable)

Elbaite tourmaline, Na(Li,Al)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄

Blue-green tourmaline (likely indicolite) (Elbaite tourmaline, Na(Li1.5Al1.5)Al6(BO3)3Si6O18(OH)4) — gemstone

Blue-green tourmaline (likely indicolite)

Elbaite tourmaline, Na(Li1.5Al1.5)Al6(BO3)3Si6O18(OH)4

Lepidolite with Tourmaline in Quartz Matrix (K(Li,Al)3(Si,Al)4O10(F,OH)2 (Lepidolite) / SiO2 (Quartz)) — mineral

Lepidolite with Tourmaline in Quartz Matrix

K(Li,Al)3(Si,Al)4O10(F,OH)2 (Lepidolite) / SiO2 (Quartz)

Blue Aragonite (Aragonite (Calcium Carbonate, CaCO3)) — mineral

Blue Aragonite

Aragonite (Calcium Carbonate, CaCO3)

Amazonite (Lead-bearing Microcline (KAlSi3O8)) — mineral

Amazonite

Lead-bearing Microcline (KAlSi3O8)

Emerald in Matrix (Beryl (Be3Al2Si6O18) containing Chromium/Vanadium impurities) — mineral

Emerald in Matrix

Beryl (Be3Al2Si6O18) containing Chromium/Vanadium impurities

Blue Kyanite (Kyanite (Al2SiO5)) — mineral

Blue Kyanite

Kyanite (Al2SiO5)

Prehnite (Prehnite (Ca2Al2Si3O10(OH)2)) — mineral

Prehnite

Prehnite (Ca2Al2Si3O10(OH)2)

Sodalite (Sodalite - Na8(Al6Si6O24)Cl2) — mineral

Sodalite

Sodalite - Na8(Al6Si6O24)Cl2

Red calcite (Calcite (CaCO₃), likely iron- or manganese-colored) — mineral

Red calcite

Calcite (CaCO₃), likely iron- or manganese-colored