Rock Identifier

Category

Rock (Likely Sedimentary)

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

Learn about Rock (Likely Sedimentary) in the encyclopedia

Asphalt Rock

Rock Gypsum

Conglomerate

Breccia

Ironstone

Limestone

Claystone

Phosphorite

Chert

Coal

Pisolite

Mudstone

Likely obsidian (black volcanic glass) (Obsidian; predominantly rhyolitic volcanic glass, often ~70–75% SiO₂) — igneous

Likely obsidian (black volcanic glass)

Obsidian; predominantly rhyolitic volcanic glass, often ~70–75% SiO₂

Sandstone (Arenite (SiO2 based typically)) — sedimentary

Sandstone

Arenite (SiO2 based typically)

Sandstone (likely Quartzite-grade) (Arenite (primarily SiO2)) — sedimentary

Sandstone (likely Quartzite-grade)

Arenite (primarily SiO2)

Jasper (Silicon dioxide (SiO2)) — sedimentary

Jasper

Silicon dioxide (SiO2)

Red Jasper (River Polished Quartzite) (Silicon Dioxide (SiO2) with Ferric Oxide (Fe2O3) impurities) — sedimentary

Red Jasper (River Polished Quartzite)

Silicon Dioxide (SiO2) with Ferric Oxide (Fe2O3) impurities

Basaltic volcanic pebble (Fine-grained mafic igneous rock, chiefly plagioclase and pyroxene, commonly with olivine and iron-titanium oxides) — igneous

Basaltic volcanic pebble

Fine-grained mafic igneous rock, chiefly plagioclase and pyroxene, commonly with olivine and iron-titanium oxides

Sandstone (Sedimentary rock composed mainly of sand-sized minerals or rock grains) — sedimentary

Sandstone

Sedimentary rock composed mainly of sand-sized minerals or rock grains

Glacial erratic boulder (Likely weathered sandstone or quartzitic sandstone; exact identification requires a fresh surface and locality) — sedimentary

Glacial erratic boulder

Likely weathered sandstone or quartzitic sandstone; exact identification requires a fresh surface and locality

Pink agate (likely dyed or coated) (Microcrystalline quartz, SiO₂ (chalcedony/agate)) — mineral

Pink agate (likely dyed or coated)

Microcrystalline quartz, SiO₂ (chalcedony/agate)

Yellow Chert or Jasper (Silicon Dioxide (SiO2)) — sedimentary

Yellow Chert or Jasper

Silicon Dioxide (SiO2)

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

Chert Arrowhead (Projectile Point)

Microcrystalline Quartz (SiO2)

Tumbled green-and-white stone, likely serpentine (Serpentinite; chiefly serpentine-group minerals (antigorite, lizardite, or chrysotile), commonly with magnetite and carbonate veins) — metamorphic

Tumbled green-and-white stone, likely serpentine

Serpentinite; chiefly serpentine-group minerals (antigorite, lizardite, or chrysotile), commonly with magnetite and carbonate veins

Fossiliferous Limestone (Limestone (CaCO3) with Crinoid/Bivalve fossils) — sedimentary

Fossiliferous Limestone

Limestone (CaCO3) with Crinoid/Bivalve fossils

Tumbled dark river pebble, probably basalt (Fine-grained mafic volcanic rock, most likely basalt; exact identification requires testing) — igneous

Tumbled dark river pebble, probably basalt

Fine-grained mafic volcanic rock, most likely basalt; exact identification requires testing

Chert (Lake Superior Agate variant) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Lake Superior Agate variant)

Microcrystalline Quartz (SiO2)

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

Chert / Flint

Microcrystalline Quartz (SiO2)

Picture Jasper (Silicon Dioxide (SiO2) with iron oxide and clay impurities) — sedimentary

Picture Jasper

Silicon Dioxide (SiO2) with iron oxide and clay impurities

Sandstone with Quartz Veins (Arenite (primarily SiO2 with Fe2O3 staining)) — sedimentary

Sandstone with Quartz Veins

Arenite (primarily SiO2 with Fe2O3 staining)

Conglomerate (with Jasper pebble) (Conglomerate / Microcrystalline Quartz (Jasper)) — sedimentary

Conglomerate (with Jasper pebble)

Conglomerate / Microcrystalline Quartz (Jasper)

Jasper (Silicon Dioxide (Microcrystalline Quartz / Chalcedony)) — sedimentary

Jasper

Silicon Dioxide (Microcrystalline Quartz / Chalcedony)

Granite or granitic gneiss pebble (Coarse-grained quartz–feldspar–mica rock; likely granite, possibly foliated gneiss) — igneous

Granite or granitic gneiss pebble

Coarse-grained quartz–feldspar–mica rock; likely granite, possibly foliated gneiss

Jasper in Quartzite (likely Cinnabar or Iron inclusions) (Silicon dioxide (SiO2) with impurities) — metamorphic

Jasper in Quartzite (likely Cinnabar or Iron inclusions)

Silicon dioxide (SiO2) with impurities

Sandstone (likely Siltstone variety) (Arenite / Siltstone (primary mineral SiO2)) — sedimentary

Sandstone (likely Siltstone variety)

Arenite / Siltstone (primary mineral SiO2)

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

Sandstone

Clastic sedimentary rock (SiO2 primary)

Weathered quartz-rich metamorphic rock (probable quartzite) (Quartzite; predominantly microcrystalline quartz (SiO₂), with possible mica, feldspar, and iron-oxide impurities) — metamorphic

Weathered quartz-rich metamorphic rock (probable quartzite)

Quartzite; predominantly microcrystalline quartz (SiO₂), with possible mica, feldspar, and iron-oxide impurities

Banded Gneiss (Gneiss (Metamorphic Rock)) — metamorphic

Banded Gneiss

Gneiss (Metamorphic Rock)

Geode (Unopened) (Siliceous Geode (SiO2)) — sedimentary

Geode (Unopened)

Siliceous Geode (SiO2)

Sandstone pebble (Sandstone (SiO2 with iron oxides)) — sedimentary

Sandstone pebble

Sandstone (SiO2 with iron oxides)

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

Quartz (Chert / Agate / Chalcedony)

Silicon Dioxide (SiO2)

Red Jasper or Ironstone concretion (SiO2 or Fe2O3) — sedimentary or mineral

Red Jasper or Ironstone concretion

SiO2 or Fe2O3

sedimentary or mineral

Blue Apatite (Fluorapatite (Ca5(PO4)3F)) — mineral

Blue Apatite

Fluorapatite (Ca5(PO4)3F)

Green Opal (Hydrated Silica (SiO2·nH2O)) — mineraloid

Green Opal

Hydrated Silica (SiO2·nH2O)

Sandstone (Sedimentary Rock (Quartz Sandstone)) — sedimentary

Sandstone

Sedimentary Rock (Quartz Sandstone)

Fossilized bone, likely a tooth or jaw fragment (Mineralized vertebrate bone; taxonomic identification requires clearer diagnostic anatomy) — fossil

Fossilized bone, likely a tooth or jaw fragment

Mineralized vertebrate bone; taxonomic identification requires clearer diagnostic anatomy

River Pebble (Siltstone / Fine-grained Sandstone) (Sedimentary Pebble (Siliclastic)) — sedimentary

River Pebble (Siltstone / Fine-grained Sandstone)

Sedimentary Pebble (Siliclastic)

Sandstone (Arenite (SiO2 primarily)) — sedimentary

Sandstone

Arenite (SiO2 primarily)

Sandstone (Arenite) — sedimentary

Sandstone

Arenite

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

Quartz (Fieldstone/Pebble)

Silicon Dioxide (SiO2)

Banded agate or jasper fragment (Microcrystalline quartz, SiO₂ (likely iron-stained chalcedony)) — mineral

Banded agate or jasper fragment

Microcrystalline quartz, SiO₂ (likely iron-stained chalcedony)

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

Yellow Quartzite (Onyx Pebble)

Silicon Dioxide (SiO2) - Quartzite

Jasper (Silicon Dioxide (Microcrystalline Quartz, SiO2)) — sedimentary

Jasper

Silicon Dioxide (Microcrystalline Quartz, SiO2)

Red Sandstone Pebble (Quartzose Sandstone) — sedimentary

Red Sandstone Pebble

Quartzose Sandstone