Rock Identifier

Category

Mineral (Primary Constituent)

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

Magnetite (Lodestone variety) (Magnetite (Iron(II,III) oxide, Fe3O4)) — mineral

Magnetite (Lodestone variety)

Magnetite (Iron(II,III) oxide, Fe3O4)

Limonite (Iron Ore) (Limonite (FeO(OH)·nH2O)) — mineral

Limonite (Iron Ore)

Limonite (FeO(OH)·nH2O)

Native Sulfur (Sulfur (S8)) — mineral

Native Sulfur

Sulfur (S8)

Granite Cobble (River Stone) (Felsic intrusive igneous rock (composition: Quartz, Feldspar, Mica)) — igneous

Granite Cobble (River Stone)

Felsic intrusive igneous rock (composition: Quartz, Feldspar, Mica)

Blue Sapphire (Corundum (Al2O3)) — mineral

Blue Sapphire

Corundum (Al2O3)

Quartz (Milky/Common) (Silicon Dioxide (SiO2)) — mineral

Quartz (Milky/Common)

Silicon Dioxide (SiO2)

Diamond in Kimberlite (Kimberlite host rock with C (Carbon) inclusion) — igneous

Diamond in Kimberlite

Kimberlite host rock with C (Carbon) inclusion

Quartz Vein in Host Rock (Likely Slate or Shale) (Hydrothermal Quartz (SiO2) in Pelitic host rock) — metamorphic

Quartz Vein in Host Rock (Likely Slate or Shale)

Hydrothermal Quartz (SiO2) in Pelitic host rock

Sandstone (with Iron Staining) (Clastic sedimentary rock (primarily Quartz with Fe2O3 staining)) — sedimentary

Sandstone (with Iron Staining)

Clastic sedimentary rock (primarily Quartz with Fe2O3 staining)

Coarse Sand Grain / Lithic Fragment (Clastic Sediment (Lithic fragment or Quartz/Feldspar grain)) — sedimentary

Coarse Sand Grain / Lithic Fragment

Clastic Sediment (Lithic fragment or Quartz/Feldspar grain)

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

Magnetite / Iron Ore

Magnetite (Fe3O4)

Greenstone / Diabase Porphyry (Porphyritic Diabase (Micro-gabbro)) — Igneous

Greenstone / Diabase Porphyry

Porphyritic Diabase (Micro-gabbro)

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

Celestite

Celestine (Strontium Sulfate, SrSO4)

Pyrite (on a metal substrate) (Iron Sulfide (FeS2)) — mineral

Pyrite (on a metal substrate)

Iron Sulfide (FeS2)

Quartz Geode (Silicon Dioxide (SiO2)) — mineral

Quartz Geode

Silicon Dioxide (SiO2)

Vesicular Basalt (Scoria) (Extrusive Mafic Volcanic Rock (FeO-SiO2-MgO)) — Igneous

Vesicular Basalt (Scoria)

Extrusive Mafic Volcanic Rock (FeO-SiO2-MgO)

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

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Amazonite (K(AlSi3O8), Microcline (potassium feldspar)) — mineral

Amazonite

K(AlSi3O8), Microcline (potassium feldspar)

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

Olivine (Peridotite)

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

Granite (Phaneritic Felsic Intrusive Rock) — igneous

Granite

Phaneritic Felsic Intrusive Rock

Shale (Argillaceous Rock) — sedimentary

Shale

Argillaceous Rock

Celestite (Celestine) (Strontium sulfate (SrSO4)) — mineral

Celestite (Celestine)

Strontium sulfate (SrSO4)

Sandstone (Arenite) — sedimentary

Sandstone

Arenite

Iron Ore (Goethite and Hematite) (Iron Oxyhydroxide (α-FeO(OH)) and Iron(III) oxide (Fe2O3)) — sedimentary

Iron Ore (Goethite and Hematite)

Iron Oxyhydroxide (α-FeO(OH)) and Iron(III) oxide (Fe2O3)

Sandstone (Clastic sedimentary rock (SiO2 primary)) — sedimentary

Sandstone

Clastic sedimentary rock (SiO2 primary)

Granite (Granite (Felsic Intrusive Igneous Rock)) — igneous

Granite

Granite (Felsic Intrusive Igneous Rock)

Barite (Desert Rose or Cockscomb variety) (Barium Sulfate (BaSO4)) — mineral

Barite (Desert Rose or Cockscomb variety)

Barium Sulfate (BaSO4)

Diamond (or Cubic Zirconia simulant) (Carbon (C) - Diamond / Zirconium dioxide (ZrO2) - CZ) — mineral

Diamond (or Cubic Zirconia simulant)

Carbon (C) - Diamond / Zirconium dioxide (ZrO2) - CZ

Sapphire (Corundum) (Corundum (Al2O3)) — mineral

Sapphire (Corundum)

Corundum (Al2O3)

Basalt (Aphanitic Mafic Igneous Rock) — igneous

Basalt

Aphanitic Mafic Igneous Rock

Limestone (Sedimentary rock composed of Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Sedimentary rock composed of Calcium Carbonate (CaCO3)

Chert (Flint) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Flint)

Microcrystalline Quartz (SiO2)

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

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Marble (Marbles are primarily composed of calcite (calcium carbonate, CaCO3) or dolomite (calcium magnesium carbonate, CaMg(CO3)2).) — Metamorphic Rock

Marble

Marbles are primarily composed of calcite (calcium carbonate, CaCO3) or dolomite (calcium magnesium carbonate, CaMg(CO3)2).

Metamorphic Rock

Cubic Zirconia (CZ) Jewelry (Zirconium dioxide (ZrO2)) — mineral (synthetic)

Cubic Zirconia (CZ) Jewelry

Zirconium dioxide (ZrO2)

mineral (synthetic)

Sandstone (likely Greywacke or Lithic Sandstone) (Arenite / Wacke) — sedimentary

Sandstone (likely Greywacke or Lithic Sandstone)

Arenite / Wacke

Larimar (Blue Pectolite (NaCa2Si3O8(OH))) — mineral

Larimar

Blue Pectolite (NaCa2Si3O8(OH))

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

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Gold and Silver (in jewelry form) (Gold (Au) and Silver (Ag)) — mineral

Gold and Silver (in jewelry form)

Gold (Au) and Silver (Ag)

Agate (Chalcedony (cryptocrystalline variety of Quartz, SiO2)) — mineral

Agate

Chalcedony (cryptocrystalline variety of Quartz, SiO2)

Yellow Quartz (Citrine appearance) (Silicon Dioxide (SiO2)) — mineral

Yellow Quartz (Citrine appearance)

Silicon Dioxide (SiO2)

Gold Nugget (Native Gold (Au)) — mineral

Gold Nugget

Native Gold (Au)