Rock Identifier

Category

Mineralogical Specimen

Browse mineralogical specimen specimens identified by the Rock Identifier community.

Coal (Anthracite) (Anthracite (Carbon-based organic sedimentary/metamorphic rock)) — metamorphic

Coal (Anthracite)

Anthracite (Carbon-based organic sedimentary/metamorphic rock)

Quartz Geode (Silicon Dioxide (SiO2)) — mineral

Quartz Geode

Silicon Dioxide (SiO2)

Clear Quartz (Silicon Dioxide (SiO2)) — mineral

Clear Quartz

Silicon Dioxide (SiO2)

Milky Quartz with Mineral Inclusions (Silicon Dioxide (SiO2) with miscellaneous inclusions) — mineral

Milky Quartz with Mineral Inclusions

Silicon Dioxide (SiO2) with miscellaneous inclusions

Green Aventurine (Silicon Dioxide (SiO2) with inclusions of Fuchsite (K(Al,Cr)2(AlSi3O10)(OH)2)) — metamorphic

Green Aventurine

Silicon Dioxide (SiO2) with inclusions of Fuchsite (K(Al,Cr)2(AlSi3O10)(OH)2)

Carnelian Agate (Silicon Dioxide (SiO2) with Iron Oxide impurities) — mineral

Carnelian Agate

Silicon Dioxide (SiO2) with Iron Oxide impurities

Quartz Pebble (Silicon Dioxide (SiO2)) — mineral

Quartz Pebble

Silicon Dioxide (SiO2)

Magnetite (likely in Hematite or Ironstone) (Magnetite (Fe3O4)) — mineral

Magnetite (likely in Hematite or Ironstone)

Magnetite (Fe3O4)

Quartz / Citrine Quartz (Silicon Dioxide (SiO2)) — mineral

Quartz / Citrine Quartz

Silicon Dioxide (SiO2)

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

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Granite (Granite) — Igneous

Granite

Granite

Breciated Howlite (Calcium borosilicate hydroxide (Ca2B5SiO9(OH)5)) — Mineral

Breciated Howlite

Calcium borosilicate hydroxide (Ca2B5SiO9(OH)5)

Quartz (Milky/Iron-stained) (Silicon Dioxide (SiO2)) — mineral

Quartz (Milky/Iron-stained)

Silicon Dioxide (SiO2)

Chalcedony (Agate/Carnelian type) (Silicon Dioxide (SiO2)) — mineral

Chalcedony (Agate/Carnelian type)

Silicon Dioxide (SiO2)

Milky Quartz with Iron Staining (Silicon Dioxide (SiO2)) — mineral

Milky Quartz with Iron Staining

Silicon Dioxide (SiO2)

Muscovite Schist with Quartz (KAl2(AlSi3O10)(OH)2 in Schistose matrix) — metamorphic

Muscovite Schist with Quartz

KAl2(AlSi3O10)(OH)2 in Schistose matrix

Banded Agate (Agatized Geode Slice) (Silicon Dioxide (SiO₂)) — mineral

Banded Agate (Agatized Geode Slice)

Silicon Dioxide (SiO₂)

Obsidian (Volcanic Glass (Silicon Dioxide with impurities)) — igneous

Obsidian

Volcanic Glass (Silicon Dioxide with impurities)

Quartzite Pebble (Quartzite (primarily SiO2)) — metamorphic

Quartzite Pebble

Quartzite (primarily SiO2)

Chert Pebble (Microcrystalline quartz (SiO2)) — sedimentary

Chert Pebble

Microcrystalline quartz (SiO2)

Labradorite (Labradorite ((Ca, Na)(Al, Si)4O8)) — mineral

Labradorite

Labradorite ((Ca, Na)(Al, Si)4O8)

Chert (Flint) (Chert (SiO2)) — sedimentary

Chert (Flint)

Chert (SiO2)

Banded Agate (specifically Gobi Eyes or Eye Agate) (Silicon Dioxide (SiO2) - Variety of Chalcedony) — mineral

Banded Agate (specifically Gobi Eyes or Eye Agate)

Silicon Dioxide (SiO2) - Variety of Chalcedony

Quartzite (Quartzite (primarily SiO2)) — metamorphic

Quartzite

Quartzite (primarily SiO2)

Gneiss (Stream-worn Cobble) (Gneiss (Metamorphic rock composed primarily of Quartz, Feldspar, and Mica)) — metamorphic

Gneiss (Stream-worn Cobble)

Gneiss (Metamorphic rock composed primarily of Quartz, Feldspar, and Mica)

Quartz (Smoky/Milky variety) (Silicon Dioxide (SiO2)) — mineral

Quartz (Smoky/Milky variety)

Silicon Dioxide (SiO2)

Sandstone (Arenite (predominantly SiO2)) — sedimentary

Sandstone

Arenite (predominantly SiO2)

Amethyst (Silicon dioxide with iron impurities (SiO2:Fe3+)) — mineral

Amethyst

Silicon dioxide with iron impurities (SiO2:Fe3+)

Fired Clay Brick (Anthropic Rock substitute) (Anthropogenic polycrystalline ceramic (predominantly Mullite and Quartz: Al6Si2O13 + SiO2)) — metamorphic (man-made / anthropic)

Fired Clay Brick (Anthropic Rock substitute)

Anthropogenic polycrystalline ceramic (predominantly Mullite and Quartz: Al6Si2O13 + SiO2)

metamorphic (man-made / anthropic)

Quartz Pebble (Silicon Dioxide (SiO2)) — mineral

Quartz Pebble

Silicon Dioxide (SiO2)

Sandstone (Weathered Pebble) (Arenite (primarily SiO2)) — sedimentary

Sandstone (Weathered Pebble)

Arenite (primarily SiO2)

Basalt (Basalt (Mafic Extrusive)) — igneous

Basalt

Basalt (Mafic Extrusive)

Asphalt Concrete (Bituminous Conglomerate) (Anthropogenic Bituminous Conglomerate) — sedimentary

Asphalt Concrete (Bituminous Conglomerate)

Anthropogenic Bituminous Conglomerate

Limonite (with Pyrite) (Limonite (Hydrated Iron Oxide) - FeO(OH)·nH2O) — mineral

Limonite (with Pyrite)

Limonite (Hydrated Iron Oxide) - FeO(OH)·nH2O

Green Moss Agate (Silicon Dioxide with inclusions (SiO2)) — sedimentary

Green Moss Agate

Silicon Dioxide with inclusions (SiO2)

Petrified Wood (Silicified Wood (primarily Chalcedony or Quartz, SiO2)) — mineral/sedimentary

Petrified Wood

Silicified Wood (primarily Chalcedony or Quartz, SiO2)

mineral/sedimentary

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

Almandine Garnet in Matrix

Almandine Garnet (Fe3Al2(SiO4)3)

Septarian (Dragon Stone) (Septarian concretion (Calcite, Aragonite, and Limestone)) — sedimentary

Septarian (Dragon Stone)

Septarian concretion (Calcite, Aragonite, and Limestone)

Quartz (Rock Crystal) with minor impurities (Quartz (SiO2)) — Mineral

Quartz (Rock Crystal) with minor impurities

Quartz (SiO2)

Milky Quartz (Gold-bearing Prospecting Specimen) (Silicon Dioxide (SiO2)) — mineral

Milky Quartz (Gold-bearing Prospecting Specimen)

Silicon Dioxide (SiO2)

River Quartz (Milky and Smoky mix) (Silicon Dioxide (SiO2)) — mineral

River Quartz (Milky and Smoky mix)

Silicon Dioxide (SiO2)

Quartz (Milky/Iron-stained) (Silicon Dioxide (SiO2)) — mineral

Quartz (Milky/Iron-stained)

Silicon Dioxide (SiO2)