Rock Identifier

Category

Rock (Likely Sedimentary)

Browse rock (likely sedimentary) specimens identified by the Rock Identifier community.

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

Quartz (Milky/Clear variety)

Silicon Dioxide (SiO2)

Botryoidal Black Chalcedony Geode (Black Grape Agate) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — Mineral

Botryoidal Black Chalcedony Geode (Black Grape Agate)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Banded Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Banded Chert

Microcrystalline Quartz (SiO2)

Granite (Weathered River Rock) (Plutonic Igneous Rock (primarily Quartz, Feldspar, and Mica)) — igneous

Granite (Weathered River Rock)

Plutonic Igneous Rock (primarily Quartz, Feldspar, and Mica)

Conglomerate (Conglomerate (a clastic sedimentary rock)) — Sedimentary Rock

Conglomerate

Conglomerate (a clastic sedimentary rock)

Sedimentary Rock

Scoria (with likely iron oxidation) (Scoria (Basaltic Scoria)) — igneous

Scoria (with likely iron oxidation)

Scoria (Basaltic Scoria)

Ferruginous Sandstone (with possible trace fossils) (Arenite with Iron-Oxide Cement (SiO2 with Fe2O3)) — sedimentary

Ferruginous Sandstone (with possible trace fossils)

Arenite with Iron-Oxide Cement (SiO2 with Fe2O3)

River Rocks (Basalt and Sedimentary Stones) (Mafic Igneous Rock (Basalt) and Clastic Sedimentary Rock) — igneous and sedimentary

River Rocks (Basalt and Sedimentary Stones)

Mafic Igneous Rock (Basalt) and Clastic Sedimentary Rock

igneous and sedimentary

Quartz (in matrix) (Quartz (SiO₂)) — mineral

Quartz (in matrix)

Quartz (SiO₂)

Amygdaloidal Rhyolite (often called Lake Superior Agate relative) (Rhyolite with Calcite/Quartz amygdules (SiO2 and secondary minerals)) — igneous

Amygdaloidal Rhyolite (often called Lake Superior Agate relative)

Rhyolite with Calcite/Quartz amygdules (SiO2 and secondary minerals)

Quartz (Fieldstone/Pebble) (Silicon Dioxide (SiO2)) — mineral

Quartz (Fieldstone/Pebble)

Silicon Dioxide (SiO2)

Granite (likely a river or beach pebble) (Granite (a felsic intrusive igneous rock primarily composed of quartz, feldspar, and mica)) — Igneous

Granite (likely a river or beach pebble)

Granite (a felsic intrusive igneous rock primarily composed of quartz, feldspar, and mica)

Blue Agate (Tumbled and Dyed) (Silicon Dioxide (SiO2) with likely organic dyes) — mineral

Blue Agate (Tumbled and Dyed)

Silicon Dioxide (SiO2) with likely organic dyes

Granite (Pink/Potassium-rich) (Phaneritic Plutonic Felsic Igneous Rock (primarily SiO2 with KAlSi3O8)) — igneous

Granite (Pink/Potassium-rich)

Phaneritic Plutonic Felsic Igneous Rock (primarily SiO2 with KAlSi3O8)

Fossil Bivalve Shell (Class Bivalvia (e.g., Veneriidae family)) — sedimentary

Fossil Bivalve Shell

Class Bivalvia (e.g., Veneriidae family)

Pumice (Vesicular volcanic glass (primarily SiO2 with Al2O3)) — Igneous

Pumice

Vesicular volcanic glass (primarily SiO2 with Al2O3)

Copper-bearing Quartz (likely Chrysocolla or Malachite staining) (Cuprite, Chrysocolla (Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O) or Malachite staining on Quartz/Host Rock) — mineral

Copper-bearing Quartz (likely Chrysocolla or Malachite staining)

Cuprite, Chrysocolla (Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O) or Malachite staining on Quartz/Host Rock

Druzy Quartz on Chert/Siltstone (Silicon Dioxide (SiO2) on Microcrystalline Silica/Siltstone matrix) — sedimentary

Druzy Quartz on Chert/Siltstone

Silicon Dioxide (SiO2) on Microcrystalline Silica/Siltstone matrix

Chert (often called Flint or River Pebble) (Chert (Microcrystalline Quartz, SiO2)) — sedimentary

Chert (often called Flint or River Pebble)

Chert (Microcrystalline Quartz, SiO2)

Coquina (Fossiliferous Limestone) (Coquina (Organic Clastic Limestone)) — sedimentary

Coquina (Fossiliferous Limestone)

Coquina (Organic Clastic Limestone)

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

Banded Chert (Flint)

Microcrystalline Quartz (SiO2)

Chert (Common Variety, Jasper) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Common Variety, Jasper)

Microcrystalline Quartz (SiO2)

Chert Pebble (Jasper/Quartz variety) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert Pebble (Jasper/Quartz variety)

Microcrystalline Quartz (SiO2)

Shale (Fissile Mudstone) — sedimentary

Shale

Fissile Mudstone

Sandstone (Ferruginous) (Clastic Sedimentary Rock (SiO2 with Fe2O3/FeOOH cement)) — sedimentary

Sandstone (Ferruginous)

Clastic Sedimentary Rock (SiO2 with Fe2O3/FeOOH cement)

Satin Spar (Selenite) (Gypsum (CaSO4·2H2O)) — mineral

Satin Spar (Selenite)

Gypsum (CaSO4·2H2O)

Chert (Arrowhead Fragment) (Chert / Microcrystalline Silicon Dioxide (SiO2)) — sedimentary

Chert (Arrowhead Fragment)

Chert / Microcrystalline Silicon Dioxide (SiO2)

Fossiliferous Limestone (Gritstone/Marl) (CaCO3 (Calcium Carbonate) with Fossil Inclusions) — sedimentary

Fossiliferous Limestone (Gritstone/Marl)

CaCO3 (Calcium Carbonate) with Fossil Inclusions

Sandstone (specifically Banded Sandstone) (Clastic sedimentary rock (primarily SiO2)) — sedimentary

Sandstone (specifically Banded Sandstone)

Clastic sedimentary rock (primarily SiO2)

Quartz Geode (Silicon Dioxide (SiO2) within a geode) — mineral

Quartz Geode

Silicon Dioxide (SiO2) within a geode

Metaconglomerate (Protolith: Conglomerate (comprising SiO2, Al2O3, etc.)) — metamorphic

Metaconglomerate

Protolith: Conglomerate (comprising SiO2, Al2O3, etc.)

Granite (Weathered) (Phaneritic Plutonic Rock (primarily Quartz, Feldspar, and Mica)) — igneous

Granite (Weathered)

Phaneritic Plutonic Rock (primarily Quartz, Feldspar, and Mica)

Granite (specifically Pink Granite) (Phaneritic Plutonic Rock (High Potassium Feldspar Granite)) — igneous

Granite (specifically Pink Granite)

Phaneritic Plutonic Rock (High Potassium Feldspar Granite)

Yellow Quartzite (Onyx Pebble) (Silicon Dioxide (SiO2) - Quartzite) — metamorphic

Yellow Quartzite (Onyx Pebble)

Silicon Dioxide (SiO2) - Quartzite

Sandstone (Banded Sandstone) (Clastic Sedimentary Rock (primarily SiO2 with iron oxide impurities)) — sedimentary

Sandstone (Banded Sandstone)

Clastic Sedimentary Rock (primarily SiO2 with iron oxide impurities)

Quartz (Quartz (SiO2 - Silicon Dioxide)) — Mineral, often found as detrital grains in sedimentary rocks

Quartz

Quartz (SiO2 - Silicon Dioxide)

Mineral, often found as detrital grains in sedimentary rocks

Pink Garnet (likely Almandine or Rhodolite) (Garnet Group (Fe3Al2(SiO4)3 to Mg3Al2(SiO4)3)) — mineral

Pink Garnet (likely Almandine or Rhodolite)

Garnet Group (Fe3Al2(SiO4)3 to Mg3Al2(SiO4)3)

Chert Arrowhead (Projectile Point) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert Arrowhead (Projectile Point)

Microcrystalline Quartz (SiO2)

Sandstone (Micaceous) (Arenite (composed primarily of SiO2)) — sedimentary

Sandstone (Micaceous)

Arenite (composed primarily of SiO2)

Sandstone (Ferruginous) (Arenite (SiO2 with iron oxide impurities)) — sedimentary

Sandstone (Ferruginous)

Arenite (SiO2 with iron oxide impurities)

Granite (Alkali-feldspar rich) (Phaneritic Felsic Igneous Rock (Major components: KAlSi3O8, SiO2)) — igneous

Granite (Alkali-feldspar rich)

Phaneritic Felsic Igneous Rock (Major components: KAlSi3O8, SiO2)

Sandstone (with Iron Staining) (Clastic Sedimentary Rock (primarily Quartz, SiO2)) — sedimentary

Sandstone (with Iron Staining)

Clastic Sedimentary Rock (primarily Quartz, SiO2)