Concretion
Sedimentary Concretion
Category
Browse sedimentary (imitation) specimens identified by the Rock Identifier community.
Concretion
Sedimentary Concretion
Conglomerate
Sedimentary Conglomerate
Conglomerate
Sedimentary Conglomerate
Conglomerate
Sedimentary Conglomerate
Sandstone or Limestone
Sedimentary Rock
Weathered limestone
Calcite-rich limestone, chiefly calcium carbonate (CaCO₃)
Rounded sandstone pebble
Quartz-rich sandstone, commonly arkose or lithic sandstone
Light-colored limestone
Calcitic limestone; primarily calcium carbonate (CaCO₃), mineral calcite
Conglomerate Pebble (with Chert / Quartz)
Sedimentary Conglomerate / Breccia Pebble
Chert
Microcrystalline or cryptocrystalline quartz
Yellow Calcite
Calcite (Calcium Carbonate, CaCO3)
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
Shale
Argillite / Shaly Mudstone
Shale
Shale (Lutite)
Fossil shell
Likely a fossilized marine bivalve shell; exact taxon is indeterminate from the image.
Quartz Pebble
Silicon Dioxide (SiO2)
Yellow Chalcedony / Yellow Agate
Silicon Dioxide (SiO2)
Pyrite
Iron sulfide (FeS2)
Shale
Clastic Sedimentary Rock
Shale (sub-type: Carbonaceous Shale)
Lutaceous Sedimentary Rock
Sandstone Anvil / Nutting Stone
Quartzose Sandstone (Sedimentary Rock)
Sandstone Pebble
Sandstone (SiO2 rich clastic rock)
Sandstone (Ferruginous)
Arenite (with Iron Oxide cement)
Shale
Shale (clastic sedimentary rock composed of silt and clay-sized particles)
Shale
Fissile mudstone (Shale)
Fossiliferous limestone
Bioclastic limestone, predominantly calcite (CaCO₃)
Weathered brown rock, likely sandstone or iron-rich sedimentary stone
Indeterminate siliciclastic rock; likely quartz-rich sandstone with iron-oxide cement
Brown Sandstone
Arenite (primarily Quartz and Feldspar, with Iron Oxide cement)
Ferruginous Sandstone
Arenite with Iron-Oxide cement (Fe2O3 · nH2O)
Weathered sandstone or quartz-rich sedimentary rock
Likely quartz arenite/subarkose; predominantly quartz (SiO₂) with feldspar and iron-oxide cement
Quartz-veined Sandstone
Sedimentary rock with quartz vein (SiO2)
Fossil-bearing Sedimentary Rock
Sedimentum cum fossili
Orange Calcite
Calcium Carbonate (CaCO3)
Sedimentary Breccia
Breccia (Clastic Sedimentary Rock)
Sedimentary Breccia
Clastic Breccia (CaCO3/SiO2 matrix)
Sandstone
Arenite
Shale
Argillite / Shale
Sandstone
Arenite
Silty Shale
Silty Shale (Fissile Sedimentary Rock)
Sandstone
Clastic sedimentary rock (primarily SiO2)
Shale (Ferruginous)
Laminated Mudrock (Siliciclastic Sedimentary Rock)
Shale
Mudstone (composed primarily of clay minerals like kaolinite, illite, and smectite, with quartz and calcite)