Shale
Mudstone (composed primarily of clay minerals like kaolinite, illite, and smectite, with quartz and calcite)
Category
Browse mineralized fossil specimens identified by the Rock Identifier community.
Shale
Mudstone (composed primarily of clay minerals like kaolinite, illite, and smectite, with quartz and calcite)
Petrified Wood
Silicified wood (primarily Silicon Dioxide, SiO2)
Petrified Wood
Silicified wood (primarily Silicon Dioxide, SiO2)
Petrified Wood
Silicified Wood (SiO2 - Silicon Dioxide)
Echinoid Fossil (Sea Urchin)
Echinoidea (specifically likely Schizaster or similar genus), calcium carbonate (CaCO3)
Sandstone (with potential trace fossils)
Clastic sedimentary rock (primarily SiO2)
Sandstone
Arenite (primarily composed of SiO2)
Red Sandstone
Arenite (primarily Quartz, SiO2, with Iron Oxide cementing agent)
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
Sandstone
Arenite
Sandstone with Ironstone Concretion
Arenite with Hematite/Goethite nodules (Fe2O3 / FeO(OH))
Sandstone (likely Arkose or Lithic)
Clastic sedimentary rock (primarily SiO2)
Sandstone (Quartz-rich)
Arenite (composed primarily of SiO2)
Sandstone
Arenite (SiO2 primarily)
Shale
Shale (clay-rich mudstone)
Glauconitic Sandstone (Greensand)
Glauconitic Sandstone ((K, Na)(Fe3+, Al, Mg)2(Si, Al)4O10(OH)2)
Sandstone
Arenite (SiO2 based sedimentary rock)
Ferruginous Sandstone (Ironstone)
Clastic sedimentary rock (SiO2 with Fe2O3/FeO(OH) cement)
Crushed Limestone
Sedimentary Calcium Carbonate (CaCO3)
Sandstone (River Pebble)
Arenite (primarily SiO2)
Fossil Shark Tooth (embedded in matrix)
Lamniformes (likely Cretalamna or Squalicorax) within phosphatic/calcareous matrix
Ironstone Concretion
Limonitic/Hematitic Concretion
Sandstone (likely Graywacke or Lithic Sandstone)
Arenite / Wacke (SiO2 based with lithic fragments)
Sandstone with Vitrinite/Coal inclusions
Arenite with Carbonaceous inclusions
Turritella (Gastropod Fossil)
Turritella (Genus of gastropods), CaCO3 (Calcium Carbonate or Silicified Agate)
Sandstone (Weathered Pebble)
Arenite (primarily SiO2)
Limestone (containing Fossil Mold)
Sedimentary Calcium Carbonate (CaCO3)
Fossiliferous Chert (Gryphaea Fossil)
Silicon Dioxide (SiO2) with Calcitic Mollusk Remnants
Sandstone (Weathered Cobble)
Clastic Sedimentary Rock (primarily SiO2)
Sandstone (Quartzose Sandstone)
Arenite (primarily SiO2)
Sandstone (Quartzose)
Arenite (SiO2 principal)
Shale
Shale (Lutite)
Chert Nodule (Fossiliferous Chert)
Microcrystalline Quartz (SiO2)
Limonite Concretion
Hydrated iron(III) oxide-hydroxide (FeO(OH)·nH2O)
Shale or Mudstone
Argillaceous sedimentary rock
Sandstone (Ferruginous)
Arenite with Iron Oxide cement (primarily SiO2 with Fe2O3)
Chert (White/Gray variety)
Chert (SiO2)
Chert (often called Flint when dark)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Nodule)
Microcrystalline Silica (SiO2)
Chert (specifically a flint nodule component)
Microcrystalline quartz (SiO2)
Sandstone (Quartz-rich Pebble)
Arenite (primarily SiO2)
Bituminous Coal
Organic sedimentary rock (humic coal)