Rock Identifier

Category

Sedimentary Rock (Specifically A Clastic Sedimentary Rock Formed Into A Cobble)

Browse sedimentary rock (specifically a clastic sedimentary rock formed into a cobble) specimens identified by the Rock Identifier community.

Schist (Kyanite Schist) (Kyanite-Mica Schist (primarily Al2SiO5, KAl2(AlSi3O10)(OH)2, and SiO2)) — metamorphic

Schist (Kyanite Schist)

Kyanite-Mica Schist (primarily Al2SiO5, KAl2(AlSi3O10)(OH)2, and SiO2)

metamorphic
Quartz (Druzy or Geode fragment) (Silicon Dioxide (SiO2)) — mineral

Quartz (Druzy or Geode fragment)

Silicon Dioxide (SiO2)

mineral
Chalcedony Nodule (Agate/Chert) (Chalcedony (cryptocrystalline Silicon Dioxide, SiO2)) — mineral

Chalcedony Nodule (Agate/Chert)

Chalcedony (cryptocrystalline Silicon Dioxide, SiO2)

mineral
Granitic Pegmatite (Granite Pegmatite (coarse-grained intrusive igneous rock)) — igneous

Granitic Pegmatite

Granite Pegmatite (coarse-grained intrusive igneous rock)

igneous
Basalt Porphyry (Porphyritic Basalt) — igneous

Basalt Porphyry

Porphyritic Basalt

igneous
Travertine (Calcareous Tufa (CaCO3)) — sedimentary

Travertine

Calcareous Tufa (CaCO3)

sedimentary
Limestone (Calcite-rich Sedimentary Rock (CaCO3)) — sedimentary

Limestone

Calcite-rich Sedimentary Rock (CaCO3)

sedimentary
Limestone with Calcite Veining (Calcium Carbonate (CaCO3)) — sedimentary

Limestone with Calcite Veining

Calcium Carbonate (CaCO3)

sedimentary
Sandstone (Arenite (SiO2 based with mineral cement)) — sedimentary

Sandstone

Arenite (SiO2 based with mineral cement)

sedimentary
Limestone (specifically fossiliferous/skeletal limestone) (Calcium Carbonate (CaCO3)) — sedimentary

Limestone (specifically fossiliferous/skeletal limestone)

Calcium Carbonate (CaCO3)

sedimentary
Chalcedony (Agate/Quartz) (Silicon Dioxide (SiO2)) — mineral

Chalcedony (Agate/Quartz)

Silicon Dioxide (SiO2)

mineral
Chert (Nodule) (Silicon dioxide (SiO2) - Cryptocrystalline Quartz) — sedimentary

Chert (Nodule)

Silicon dioxide (SiO2) - Cryptocrystalline Quartz

sedimentary
Jasper, possibly Brecciated Jasper or Ocean Jasper due to patterns and color (Silicon Dioxide (SiO2), a variety of Chalcedony) — Sedimentary Rock

Jasper, possibly Brecciated Jasper or Ocean Jasper due to patterns and color

Silicon Dioxide (SiO2), a variety of Chalcedony

Sedimentary Rock
Geode with Quartz Crystal Cavity (Silicon Dioxide (SiO2) in Calcareous/Siliceous Matrix) — sedimentary

Geode with Quartz Crystal Cavity

Silicon Dioxide (SiO2) in Calcareous/Siliceous Matrix

sedimentary
Dalmation Stone (Dalmation Jasper) (Peralkaline rock (primarily Feldspar and Quartz with Arfvedsonite spots)) — igneous

Dalmation Stone (Dalmation Jasper)

Peralkaline rock (primarily Feldspar and Quartz with Arfvedsonite spots)

igneous
Pink Granite (Phaneritic Felsic Igneous Rock (Rich in K-Feldspar)) — igneous

Pink Granite

Phaneritic Felsic Igneous Rock (Rich in K-Feldspar)

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

Basalt

Basalt (Mafic volcanic rock)

igneous
Quartz / Common Opal (Silicon Dioxide (SiO2)) — mineral

Quartz / Common Opal

Silicon Dioxide (SiO2)

mineral
Iron Ore / Ironstone Concretion (Mixture of iron oxide/hydroxide minerals, likely some combination of Hematite (Fe2O3), Goethite (α-FeOOH), and Limonite (a general term for hydrated iron oxides of variable composition) or potentially Bauxite (a mixture of aluminum hydroxides, often with iron oxides, (Al(OH)3) and FeO(OH)). The visual characteristics strongly suggest iron-rich material.) — Mineral, specifically an iron ore

Iron Ore / Ironstone Concretion

Mixture of iron oxide/hydroxide minerals, likely some combination of Hematite (Fe2O3), Goethite (α-FeOOH), and Limonite (a general term for hydrated iron oxides of variable composition) or potentially Bauxite (a mixture of aluminum hydroxides, often with iron oxides, (Al(OH)3) and FeO(OH)). The visual characteristics strongly suggest iron-rich material.

Mineral, specifically an iron ore
Dalmatian Stone (Peralkaline rhyolite with arfvedsonite (formerly incorrectly called Dalmatian Jasper)) — igneous

Dalmatian Stone

Peralkaline rhyolite with arfvedsonite (formerly incorrectly called Dalmatian Jasper)

igneous
Turquoise (Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]) — mineral

Turquoise

Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]

mineral
Ferruginous Siltstone or Mudstone (Ferruginous Siltstone / Goethitic Sandstone) — sedimentary

Ferruginous Siltstone or Mudstone

Ferruginous Siltstone / Goethitic Sandstone

sedimentary
Ocean Jasper (Silicon Dioxide (SiO2)) — Mineral_variety_of_Chalcedony

Ocean Jasper

Silicon Dioxide (SiO2)

Mineral_variety_of_Chalcedony
Coal (Bituminous or Anthracite) (Carbonaceous sedimentary rock (primarily Carbon, C)) — sedimentary

Coal (Bituminous or Anthracite)

Carbonaceous sedimentary rock (primarily Carbon, C)

sedimentary
River Stone (Granitic Gneiss) (Foliated Granitic Gneiss) — metamorphic

River Stone (Granitic Gneiss)

Foliated Granitic Gneiss

metamorphic
Pink Granite (Phaneritic Felsic Igneous Plutonic Rock) — igneous

Pink Granite

Phaneritic Felsic Igneous Plutonic Rock

igneous
Fossilized Gastropod (Snail) (Class Gastropoda (internal mold or 'steinkern')) — sedimentary

Fossilized Gastropod (Snail)

Class Gastropoda (internal mold or 'steinkern')

sedimentary
Granite (Granite (Felsic Plutonic Rock)) — igneous

Granite

Granite (Felsic Plutonic Rock)

igneous
Banded Agate (specifically Sardonyx Agate) (Silicon Dioxide (SiO2) - Chalcedony variety) — mineral

Banded Agate (specifically Sardonyx Agate)

Silicon Dioxide (SiO2) - Chalcedony variety

mineral
Yellow Calcite (Calcium Carbonate (CaCO3)) — mineral

Yellow Calcite

Calcium Carbonate (CaCO3)

mineral
Emerald / Green Beryl (Beryl (Be3Al2(SiO3)6) with Chromium/Vanadium impurities) — mineral

Emerald / Green Beryl

Beryl (Be3Al2(SiO3)6) with Chromium/Vanadium impurities

mineral
Quartz Geode (Cracked Open) (Quartz (Silicon Dioxide - SiO2)) — mineral

Quartz Geode (Cracked Open)

Quartz (Silicon Dioxide - SiO2)

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

Almandine Garnet

Almandine (Fe3Al2(SiO4)3)

mineral
Basalt (Basalt (Mafic volcanic rock)) — igneous

Basalt

Basalt (Mafic volcanic rock)

igneous
Chert (Jasper/Flint variant) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Jasper/Flint variant)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

sedimentary
Granite Cobble/Pebble (Granite) — Igneous

Granite Cobble/Pebble

Granite

Igneous
Granodiorite (Granodiorite (phaneritic intrusive igneous rock)) — igneous

Granodiorite

Granodiorite (phaneritic intrusive igneous rock)

igneous
Chert (Jasper variation) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Jasper variation)

Silicon Dioxide (SiO2)

sedimentary
Chert (Jasper/Iron-stained Quartzite) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Jasper/Iron-stained Quartzite)

Silicon Dioxide (SiO2)

sedimentary
Anthracite Coal (Anthracite (Carbon-rich Sedimentary Rock)) — sedimentary

Anthracite Coal

Anthracite (Carbon-rich Sedimentary Rock)

sedimentary
Mica Schist (Mica Schist (primarily Muscovite and Biotite composition)) — metamorphic

Mica Schist

Mica Schist (primarily Muscovite and Biotite composition)

metamorphic
Biotite Schist (Biotite Schist (K(Mg,Fe)3AlSi3O10(OH,F)2)) — metamorphic

Biotite Schist

Biotite Schist (K(Mg,Fe)3AlSi3O10(OH,F)2)

metamorphic