Weathered sandstone pebble
Quartz-rich sandstone, likely ferruginous sandstone
sedimentary
Category
Rock (Likely Sedimentary)
Browse rock (likely sedimentary) specimens identified by the Rock Identifier community.
Learn about Rock (Likely Sedimentary) in the encyclopedia
View all →
Chert (Jasper variation)
Silicon Dioxide (SiO2)
sedimentary
River Stone (Quartzite/Chert)
Metamorphosed Quartz-rich Sedimentary Rock
metamorphic
Weathered granitic rock
Granite or granodiorite; mainly quartz, feldspar, and mica/amphibole
igneous
Gneiss
Gneiss
metamorphic
Unidentified Rock Fragment
Unknown
Rock
Sandstone (Quartzose Sandstone)
Clastic Sedimentary Rock (primarily SiO2)
sedimentary
Garnet (Almandine)
Almandine, Fe3Al2(SiO4)3
metamorphic
Fossilized tooth, likely a mammalian tooth fragment
Indeterminate fossil tooth; possibly an ungulate or carnivoran tooth
fossil
Chert (and/or Siltstone River Pebble)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Sandstone with Magnetite and Iron Staining
Clastic Sedimentary Rock (contains Fe3O4 and Limonite/Hematite)
sedimentary
Chert (variably called Jasper or Agate)
Microcrystalline Quartz (SiO2)
sedimentary
Likely weathered gneiss
Foliated metamorphic rock, commonly quartz–feldspar–mica gneiss
metamorphic
Dark metamorphic rock, likely biotite schist or gneiss
Quartz–feldspar–biotite metamorphic rock; exact identification requires a fresh surface and testing
metamorphic
Sandstone (specifically Flagstone)
Arenite (primarily composed of SiO2)
sedimentary
Sandstone (likely Fossiliferous)
Arenite / Fossiliferous Sandstone (SiO2 composition)
sedimentary
Sandstone (likely Quartzose Sandstone)
Arenite (SiO2 based)
sedimentary
Likely quartz-rich metamorphic rock (quartzite or quartz-veined schist)
Quartzite/siliceous schist; chiefly quartz (SiO₂), with probable mica and iron-oxide staining
metamorphic
Fluorite on Matrix
Calcium Fluoride (CaF2)
mineral
Quartz (Iron-Stained)
Silicon Dioxide (SiO2)
mineral
Quartz Pebble
Crystalline Silica (SiO2)
sedimentary
Blue Chalcedony
Chalcedony (Silicon Dioxide, SiO2)
mineral
Sandstone
Arenite (SiO2 based)
sedimentary
Chert
Chert (SiO2)
sedimentary
Sandstone (Water-worn Cobble)
Arenite (variable composition, primarily SiO2)
sedimentary
Sandstone (River Cobble)
Clastic sedimentary rock (primarily SiO2 with various lithic fragments)
sedimentary
Chert Nodules with Iron Staining
Microcrystalline Quartz (SiO2)
sedimentary
Red Sandstone
Clastic sedimentary rock (Quartz arenite/Arkose)
sedimentary
Sandstone (likely Arkosic or Lithic)
Clastic Sedimentary Rock (composed mostly of SiO2)
sedimentary
River Stone (likely Andesite or Siltstone)
Intermediate Volcanic Rock / Fine-grained Sedimentary Rock
igneous
Chert (Flint) with Quartz Vein
Silicon Dioxide (SiO2)
sedimentary
Fluorite Geode
Calcium Fluoride (CaF2)
mineral
Sandstone (likely Siltstone or Mudstone)
Clastic sedimentary rock (primarily SiO2 with various oxides)
sedimentary
Felsic Drill Core (likely Gneiss or Granite)
Felsic Metamorphic Rock (Gneissic profile)
metamorphic
Pebble (Likely Basalt or Siltstone)
Clastic sedimentary rock or mafic volcanic rock
Igneous or Sedimentary
Fossiliferous Limestone
Carbonate Rock (CaCO3 with organic inclusions)
sedimentary
Weathered iron-rich rock, likely limonite-bearing sandstone or laterite
Limonite/goethite-rich ferruginous rock; composition commonly FeO(OH)·nH₂O with quartz and clay minerals
sedimentary
Fossilized Bored Limestone
Limestone with Ichnofossils (Gastrochaenolites or Entobia)
sedimentary
Weathered foliated metamorphic rock, likely gneiss or schist
Quartz–feldspar–mica metamorphic rock; exact identification requires a fresh surface and mineral tests
metamorphic
Yellow Quartz (Chalcedony or Agate)
Silicon Dioxide (SiO2)
mineral
Quartz Geode / Druzy Quartz
Silicon Dioxide (SiO2)
mineral
Gray River Pebble (likely Limestone or Siltstone)
Sedimentary Rock (Calcium Carbonate or Siliciclastic)
sedimentary