Sandstone (Ferruginous)
Arenite (primarily SiO2 with iron oxide staining/cementing)
Category
Browse sedimentary (fossil) specimens identified by the Rock Identifier community.
Sandstone (Ferruginous)
Arenite (primarily SiO2 with iron oxide staining/cementing)
Fossilized bivalve shell fragment
Fossil Mollusca, likely a bivalve (class Bivalvia); exact genus cannot be determined from the image
Petrified Wood
Silicified Wood (SiO2 permineralization)
Petrified Wood
Silicified Wood (SiO2-dominant)
Sandstone
Arenite (primarily SiO2)
Chalcedony (Agate)
Silicon Dioxide (SiO2)
Fossilized Echinoid (Sea Urchin)
Echinoidea (Class) - Often found as Micraster or Clypeaster specimens
Fossiliferous Limestone (Murchisonia/Gastropod Limestone)
Biogenic Limestone (Calcium Carbonate, CaCO3)
Fossiliferous Shale (with Vertebrate Bones)
Laminated Mudstone containing Fossilized Bone (Apatite)
Fossiliferous Limestone (Coquina / Shell Limestone)
Biogenic Limestone (CaCO3)
Echinoid Fossil in Flint or Chert Nodule
Echinoidea embedded in sedimentary silica (SiO2)
Sandstone with Ironstone Concretion
Arenite with Ferruginous Cement
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified Wood (primarily SiO2)
Petrified Wood
Silicified wood (Quartz/Chalcedony/SiO2)
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Seashell (Cockle Shell)
Cardiidae (Bivalvia), primary composition: Calcium Carbonate (CaCO3) in the form of aragonite or calcite
Fossilized Brachiopod Shell
Order Spiriferida (likely)
Fossiliferous Limestone (Crinoid stem)
CaCO3 (Calcium Carbonate) with Fossil Inclusions
Weathered, porous limestone (probable fossiliferous limestone)
Calcite-rich limestone; predominantly CaCO₃
Petrified Wood
Silicified Wood (primarily quartz/chalcedony replacing organic wood structure, SiO2)
Crinoid Fossil in Limestone
Class Crinoidea in Carbonate Matrix (CaCO3)
Petrified Wood
Silicified Wood (primarily SiO2 - Silicon Dioxide)
Fossiliferous Limestone (Coquina / Shell Conglomerate)
Bioclastic Limestone (composed primarily of CaCO3)
Likely weathered fossil bone fragment
Indeterminate fossilized bone; taxonomic identification requires microscopy and locality data
Ironstone Concretion (Boji Stone/Moqui Marble type)
Goethite/Hematite-encrusted Sandstone Concretion
Pyrite Concretion (Grapestone)
Iron Sulfide (FeS2) Concretion
Sandstone
Arenite
Sandstone (Quartzose)
Arenite (primarily SiO2)
Limestone with Fossil Imprints
Biogenic Limestone (Calcium Carbonate, CaCO3)
Ironstone Concretion
Ironstone (Siderite/Limonite/Goethite)
Fossiliferous Rock (likely Dinosaur Fossil in Matrix)
Permineralized Vertebrate Fossil (Calcium Carbonate/Silica replaced bone material)
Fossiliferous Limestone
Bioclastic Limestone (composition: CaCO3)
Petoskey Stone
Hexagonaria percarinata (Fossilized colonial coral)
Fossiliferous Limestone
Calcium Carbonate (CaCO3) with Bioclasts
Megalodon Tooth
Otodus megalodon
Petoskey Stone
Hexagonaria percarinata (Fossilized Rugose Coral)
Chert (Fossiliferous)
Silicon dioxide (SiO2)
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Fe2O3 staining)
Sandstone (likely Graywacke or Arkose variant)
Clastic Sedimentary Rock (SiO2 with assorted lithic fragments)
Reddish Brown Claystone or Siltstone
Argillite / Siltstone / Claystone