Blue Calcite
Calcite (Calcium Carbonate, CaCO3)
Category
Browse sedimentary (biogenic) specimens identified by the Rock Identifier community.
Blue Calcite
Calcite (Calcium Carbonate, CaCO3)
Orange Calcite
Calcite (Calcium Carbonate, CaCO3)
Orange Calcite
Calcium Carbonate (CaCO3)
Satin Spar (Selenite)
Gypsum (Calcium Sulfate Dihydrate, CaSO4·2H2O)
Fossiliferous Shale
Sedimentary Clastic Rock with fossil inclusions (likely Brachiopod or Bivalve impressions)
Shale
Laminated Fissile Pelite
Sandstone
Arenite
Sandstone
Clastic Sedimentary Rock (composed mostly of SiO2)
Sandstone
Arenite (predominantly SiO2 with iron oxides)
Fossilized Shell Impression / Siltstone Fossil
Bivalvia / Brachiopoda mold in Siltstone
Fossiliferous shale or mudstone with a brachiopod fossil
Likely a spiriferid brachiopod fossil in dark shale/mudstone; exact species and age require locality and examination
Banded river pebble
Likely banded sandstone or siltstone; exact identification requires testing
Shale or Mudstone
Argillaceous sedimentary rock
Sandstone
Sandstone (principally SiO2/Silicon Dioxide)
Shale
Lutaceous Rock (Hydrous Aluminum Silicates)
Sandstone
Arenite
Sandstone
Arenite (primarily composed of SiO2)
Sandstone (with carbonaceous plant fragments)
Arenite (composed primarily of SiO2)
Shale
Fissile Siliciclastic Sedimentary Rock
Pitted Sedimentary Rock / Cupstone
Sedimentary rock with weathering pit (arenite / sandstone)
Pyrite in Shale
Iron Disulfide (FeS2)
Jasper (Chert / Chalcedony)
Silicon Dioxide (SiO2) with Iron Oxide inclusions
Pyrite
Iron Sulfide (FeS2)
Pyrite
Iron Sulfide (FeS2)
General Rock and Mineral Collection (Center: Angelite / Blue Anhydrite)
Anhydrite (Calcium Sulfate, CaSO4)
Weathered sandstone
Quartz-rich sandstone, likely ferruginous subarkose
Weathered sandstone or siltstone cobble
Clastic sedimentary rock, probably quartz-rich sandstone; exact identification requires testing
Weathered shale or mudstone
Clastic mudrock, chiefly clay minerals, quartz, and feldspar
Polished fossil-bearing shale or mudstone
Fossiliferous carbonaceous mudstone/shale; visible fossils may be bivalves or ammonites, but species cannot be confirmed from the image
Banded sandstone pebble
Quartz-rich sandstone, likely iron-oxide- and organic/mineral-stained; exact variety uncertain
Brachiopod Fossil in Limestone
Phylum Brachiopoda (likely Order Spiriferida), CaCO3 (Calcite)
Shale with Iron Staining
Fissile Mudrock (Sedimentary Rock)
Shale (with Iron Staining)
Argillaceous mudstone / Shale
Sandstone (Ferruginous)
Arenite (Fe-oxide cemented)
Sandstone (River Cobble / Pebble)
Sedimentary Rock (Quartz Sandstone / Arenite)
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Iron Oxide cement)
Shale
Fissile Mudstone
Sandstone (Ferruginous)
Clastic Sedimentary Rock (SiO2 with Fe2O3/FeOOH cement)
Banded gneiss
Gneiss, likely quartz–feldspar–mica gneiss
Weathered Sandstone Cobble
Arenite / Quartz Sandstone
Fossil Belemnite Guard
Belemnitella spp. (rostrum)
Weathered sandstone fragment
Quartz-rich sandstone (compositionally uncertain)