Rock Identifier

Category

Mineral (Primary Constituent)

Browse mineral (primary constituent) specimens identified by the Rock Identifier community.

Blue Sapphire (Tumbled/Polished) (Corundum (Al2O3)) — mineral

Blue Sapphire (Tumbled/Polished)

Corundum (Al2O3)

Pegmatite (White Granite variant) (Pegmatitic Granite (Quartz and Feldspar rich)) — igneous

Pegmatite (White Granite variant)

Pegmatitic Granite (Quartz and Feldspar rich)

Green Aventurine (Quartzite with Fuchsite inclusions (SiO2 + K(Al,Cr)2(AlSi3O10)(OH)2)) — metamorphic

Green Aventurine

Quartzite with Fuchsite inclusions (SiO2 + K(Al,Cr)2(AlSi3O10)(OH)2)

Sandstone (Arenite (composed primarily of Quartz: SiO2)) — sedimentary

Sandstone

Arenite (composed primarily of Quartz: SiO2)

Marble (Recrystallized Calcite (CaCO3)) — metamorphic

Marble

Recrystallized Calcite (CaCO3)

Sandstone (Ferruginous) (Arenite (complex silicate composition with iron oxides)) — sedimentary

Sandstone (Ferruginous)

Arenite (complex silicate composition with iron oxides)

Asphalt (Bituminous Concrete) (Bituminous mix containing aggregates and petroleum-based binder (CnH2n+2)) — not a rock (anthropogenic material/technofossil)

Asphalt (Bituminous Concrete)

Bituminous mix containing aggregates and petroleum-based binder (CnH2n+2)

not a rock (anthropogenic material/technofossil)

Limonite (Hydrous Iron Oxide (often Goethite FeO(OH), Lepidocrocite γ-FeO(OH), and other amorphous iron oxyhydroxides)) — Mineral

Limonite

Hydrous Iron Oxide (often Goethite FeO(OH), Lepidocrocite γ-FeO(OH), and other amorphous iron oxyhydroxides)

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

Specular Hematite (Specularite)

Iron(III) oxide (Fe2O3)

Red Sandstone (Arenite (Ferruginous Sandstone)) — sedimentary

Red Sandstone

Arenite (Ferruginous Sandstone)

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

Hematite

Iron(III) oxide (Fe2O3)

Granite (Granite (Felsic Plutonic Rock)) — igneous

Granite

Granite (Felsic Plutonic Rock)

Jasper (Silicon Dioxide (SiO2)) — sedimentary

Jasper

Silicon Dioxide (SiO2)

Red Hematite (Banded Iron Formation) (Hematite (Fe2O3)) — mineral

Red Hematite (Banded Iron Formation)

Hematite (Fe2O3)

Sandstone (likely Arkosic) (Clastic Sedimentary Rock) — sedimentary

Sandstone (likely Arkosic)

Clastic Sedimentary Rock

Limestone with Chert Nodules (Sedimentary Calcium Carbonate (CaCO3) with Microcrystalline Silica (SiO2) inclusions) — sedimentary

Limestone with Chert Nodules

Sedimentary Calcium Carbonate (CaCO3) with Microcrystalline Silica (SiO2) inclusions

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Ruby in Matrix (Corundum (Al2O3)) — mineral

Ruby in Matrix

Corundum (Al2O3)

Tiger's Eye (Pseudomorph of Quartz after Crocidolite (SiO2 with Iron inclusions)) — metamorphic

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2 with Iron inclusions)

Sandstone (Arenite (primarily SiO2)) — sedimentary

Sandstone

Arenite (primarily SiO2)

Magnetite / Iron Ore (Magnetite (Fe3O4)) — mineral

Magnetite / Iron Ore

Magnetite (Fe3O4)

Olivine (Peridotite) ((Mg, Fe)2SiO4 (Magnesium Iron Silicate)) — igneous

Olivine (Peridotite)

(Mg, Fe)2SiO4 (Magnesium Iron Silicate)

Specular Hematite with Quartz (Ferric oxide (Fe2O3) and Silicon dioxide (SiO2)) — Mineral

Specular Hematite with Quartz

Ferric oxide (Fe2O3) and Silicon dioxide (SiO2)

Sand (Construction Grade) (Unconsolidated siliciclastic sediment (primarily SiO2)) — sedimentary

Sand (Construction Grade)

Unconsolidated siliciclastic sediment (primarily SiO2)

Pegmatite with Smoky Quartz and Feldspar (Pegmatite (Quartz: SiO2, Feldspar: KAlSi3O8)) — igneous

Pegmatite with Smoky Quartz and Feldspar

Pegmatite (Quartz: SiO2, Feldspar: KAlSi3O8)

Gold (Gold (Au)) — Mineral

Gold

Gold (Au)

Blue Sapphire (Corundum (Al2O3) with traces of Iron and Titanium) — mineral

Blue Sapphire

Corundum (Al2O3) with traces of Iron and Titanium

Gypsum (Wallboard/Drywall) (Calcium Sulfate Dihydrate (CaSO4·2H2O)) — sedimentary

Gypsum (Wallboard/Drywall)

Calcium Sulfate Dihydrate (CaSO4·2H2O)

Pyrite (Iron Pyrite (FeS2)) — mineral

Pyrite

Iron Pyrite (FeS2)

Calcite on Limestone (or Fossil) (Calcium Carbonate (CaCO3)) — sedimentary

Calcite on Limestone (or Fossil)

Calcium Carbonate (CaCO3)

Jasper with Pyrite (Gold-colored inclusions) (Silicon Dioxide (SiO2) with Iron Disulfide (FeS2) inclusions) — sedimentary (chemical/biological)

Jasper with Pyrite (Gold-colored inclusions)

Silicon Dioxide (SiO2) with Iron Disulfide (FeS2) inclusions

sedimentary (chemical/biological)

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

Anthracite Coal

Anthracite (Carbon-rich metamorphic coal)

Granite Cobble (Granite (Phaneritic Igneous Rock)) — igneous

Granite Cobble

Granite (Phaneritic Igneous Rock)

Chert (varietal Flint) (Silicon Dioxide (SiO2)) — sedimentary

Chert (varietal Flint)

Silicon Dioxide (SiO2)

Ironstone with Limonite/Goethite coating (Ferruginous Sedimentary Rock (contains Limonite FeO(OH)·nH2O)) — sedimentary

Ironstone with Limonite/Goethite coating

Ferruginous Sedimentary Rock (contains Limonite FeO(OH)·nH2O)

Hematite Nodules (Moqui Marbles) (Ferric Oxide (Fe2O3)) — mineral

Hematite Nodules (Moqui Marbles)

Ferric Oxide (Fe2O3)

Diamond (Faceted Colorless) (Diamond (Pure Carbon, C)) — mineral

Diamond (Faceted Colorless)

Diamond (Pure Carbon, C)

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

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Blue Celestite (Celestine (Strontium Sulfate, SrSO4)) — mineral

Blue Celestite

Celestine (Strontium Sulfate, SrSO4)

White Chalcedony (Agate) (Silicon Dioxide (SiO2)) — mineral

White Chalcedony (Agate)

Silicon Dioxide (SiO2)

Hematite (Iron Ore) (Hematite (Fe2O3)) — mineral

Hematite (Iron Ore)

Hematite (Fe2O3)

Satin Spar (Selenite Gypsum Sphere) (Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O) — mineral

Satin Spar (Selenite Gypsum Sphere)

Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O