Rock Identifier

Category

Rock

Browse rock specimens identified by the Rock Identifier community.

Learn about Rock in the encyclopedia

Rock Gypsum

Coral Rock

Asphalt Rock

Rock Salt

Calc-Silicate Rock

Calc-Silicate Rock

Talc-carbonate Rock

Talc-carbonate Rock

Anorthosite

Cataclasite

Peridotite

Phosphorite

Gondite

Dunite

River Rock (Mossy) (Stream-rounded Clast (likely Siltstone or Sandstone with bryophytes)) — sedimentary

River Rock (Mossy)

Stream-rounded Clast (likely Siltstone or Sandstone with bryophytes)

River Stone / Pebble (Clastic Sediment (composed largely of Quartz, Feldspar, and various rock fragments)) — Mineral, Sediment

River Stone / Pebble

Clastic Sediment (composed largely of Quartz, Feldspar, and various rock fragments)

Mineral, Sediment

Quartz Vein in Gneiss or Schist (Metamorphic rock with SiO2 vein) — metamorphic

Quartz Vein in Gneiss or Schist

Metamorphic rock with SiO2 vein

Sandstone (Arenite (Siliclastic sedimentary rock)) — sedimentary

Sandstone

Arenite (Siliclastic sedimentary rock)

Basalt River Pebble (Mafic volcanic rock (Basalt)) — igneous

Basalt River Pebble

Mafic volcanic rock (Basalt)

Granite (Granite (Felsic Plutonic Rock)) — igneous

Granite

Granite (Felsic Plutonic Rock)

Sandstone (Arenite (SiO2 based)) — sedimentary

Sandstone

Arenite (SiO2 based)

Sandstone (Ferruginous) (Arenite with Iron Oxide matrix) — sedimentary

Sandstone (Ferruginous)

Arenite with Iron Oxide matrix

Unakite (Epidotized Granite) — metamorphic

Unakite

Epidotized Granite

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

Clear Quartz

Quartz (Silicon Dioxide, SiO2)

Graywacke (Lithic Sandstone (Graywacke)) — sedimentary

Graywacke

Lithic Sandstone (Graywacke)

Sandstone (Arenite (primarily SiO2)) — sedimentary

Sandstone

Arenite (primarily SiO2)

Quartzite (Quartzite (SiO2)) — metamorphic

Quartzite

Quartzite (SiO2)

Scoria (Lava Rock) (Scoria) — igneous

Scoria (Lava Rock)

Scoria

Granite (Phaneritic plutonic rock (Quartz, Feldspar, Mica)) — igneous

Granite

Phaneritic plutonic rock (Quartz, Feldspar, Mica)

Cockle Shell (Fossil or Recent) (Class Bivalvia, Family Cardiidae (e.g., Cerastoderma edule for common cockle)) — Sedimentary (Biogenic, a type of fossil)

Cockle Shell (Fossil or Recent)

Class Bivalvia, Family Cardiidae (e.g., Cerastoderma edule for common cockle)

Sedimentary (Biogenic, a type of fossil)

Blue Chalcedony (Silicon Dioxide (SiO2)) — mineral

Blue Chalcedony

Silicon Dioxide (SiO2)

Gastropod Steinkern (Fossilized Snail Cast) (Phylum Mollusca, Class Gastropoda (Commonly CaCO3 or SiO2 after replacement)) — Sedimentary

Gastropod Steinkern (Fossilized Snail Cast)

Phylum Mollusca, Class Gastropoda (Commonly CaCO3 or SiO2 after replacement)

Basalt (Water-worn Pebble) (Mafic Volcanic Rock (High in Fe and Mg)) — igneous

Basalt (Water-worn Pebble)

Mafic Volcanic Rock (High in Fe and Mg)

Sandstone (Arenite (SiO2 based)) — sedimentary

Sandstone

Arenite (SiO2 based)

Garnet in Host Rock (Garnet Group (A3B2(SiO4)3)) — metamorphic

Garnet in Host Rock

Garnet Group (A3B2(SiO4)3)

Porphyritic Basalt (or Andesite) containing Augite (Porphyritic Mafic Volcanic Rock) — igneous

Porphyritic Basalt (or Andesite) containing Augite

Porphyritic Mafic Volcanic Rock

Granite (Felsic intrusive igneous rock) — igneous

Granite

Felsic intrusive igneous rock

Fossil Shell (Invertebrate fossil (Mollusca)) — fossil

Fossil Shell

Invertebrate fossil (Mollusca)

Mosasaur Tooth Fossil (Mosasaurus sp.) — fossil

Mosasaur Tooth Fossil

Mosasaurus sp.

Petrified Wood (Silicified Wood (SiO2)) — fossil

Petrified Wood

Silicified Wood (SiO2)

Titanium Quartz (Aura Quartz) (Silicon Dioxide (SiO2) treated with Titanium) — mineral

Titanium Quartz (Aura Quartz)

Silicon Dioxide (SiO2) treated with Titanium

Concretion (Septarian or Siderite Concretion) — sedimentary

Concretion

Septarian or Siderite Concretion

Blue Quartz (or Blue Aventurine) (Silicon Dioxide (SiO2) with inclusions (typically Crocidolite or Dumortierite)) — mineral

Blue Quartz (or Blue Aventurine)

Silicon Dioxide (SiO2) with inclusions (typically Crocidolite or Dumortierite)

Chert (Flint) (Chert (Cryptocrystalline Silica, SiO2)) — sedimentary

Chert (Flint)

Chert (Cryptocrystalline Silica, SiO2)

Variscite in Matrix (often traded as Wardite or Cryptocrystalline Variscite) (Variscite (AlPO4·2H2O)) — mineral

Variscite in Matrix (often traded as Wardite or Cryptocrystalline Variscite)

Variscite (AlPO4·2H2O)

Unakite (Altered Granite (Epidotized Granite)) — metamorphic

Unakite

Altered Granite (Epidotized Granite)

Geode Nodules / Chert Pebble (Silicon Dioxide (SiO2) / Quartz concretion) — sedimentary

Geode Nodules / Chert Pebble

Silicon Dioxide (SiO2) / Quartz concretion

Chert (Flint / Jasper) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Flint / Jasper)

Silicon Dioxide (SiO2)

Chert (Gravel) (Chert (Microcrystalline Silicon Dioxide, SiO2)) — sedimentary

Chert (Gravel)

Chert (Microcrystalline Silicon Dioxide, SiO2)

Amethyst (Quartz (Silicon Dioxide with Iron impurities), SiO2) — mineral

Amethyst

Quartz (Silicon Dioxide with Iron impurities), SiO2

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Crinoidal Limestone (Fossiliferous Limestone containing Crinoid stem fragments (Echinodermata)) — fossil

Crinoidal Limestone

Fossiliferous Limestone containing Crinoid stem fragments (Echinodermata)

Limestone Cobble (Sedimentary Calcium Carbonate (CaCO3)) — sedimentary

Limestone Cobble

Sedimentary Calcium Carbonate (CaCO3)

Quartzite Arrowhead (Quartzite (SiO2 silicon dioxide)) — metamorphic

Quartzite Arrowhead

Quartzite (SiO2 silicon dioxide)

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

Garnet (Almandine)

Almandine (Fe3Al2(SiO4)3)

Dyed Agate (Silicon Dioxide (SiO2) with artificial pigment) — sedimentary

Dyed Agate

Silicon Dioxide (SiO2) with artificial pigment