Chalcedony (specifically Agate or Common Opal variety)
Cryptocrystalline Silica (SiO2)
Category
Browse fossil specimens identified by the Rock Identifier community.
Chalcedony (specifically Agate or Common Opal variety)
Cryptocrystalline Silica (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Sandstone Beach Pebble
Clastic Sandstone (SiO2 - Quartz-dominant)
Chert (often found as Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Red Shale
Fissile Siliciclastic Sedimentary Rock
Limestone (specifically fossiliferous/skeletal limestone)
Calcium Carbonate (CaCO3)
Sandstone (specifically Arkose or Ferruginous Sandstone)
Sandstone (SiO2 predominant)
Sandstone (with potential trace fossils)
Clastic sedimentary rock (primarily SiO2)
Chert (Chert Nodule)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Slate
Slate (Foliated Metamorphic Rock)
Vesicular Sandstone
Clastic Sedimentary Rock (Sandstone)
Ferruginous Sandstone (Gozzan/Ironstone)
Arenite with Limonite/Goethite cement (FeO(OH)·nH2O)
Sandstone (Greywacke)
Arenite / Lithic Wacke (SiO2 predominant)
Limestone (specifically Chalky Limestone)
Calcium Carbonate (CaCO3 / Calcite)
Sandstone (with Chert/Quartzite)
Arenite (primarily SiO2)
Sandstone (with Feldspathic/Arkose qualities)
Arenite (primarily SiO2 with KAlSi3O8 components)
Limestone
Calcium Carbonate (CaCO3)
Limestone
Calcium Carbonate (CaCO3)
Sandstone (Quartzose)
Arenite (SiO2 based)
Red Siltstone (or Red Shale)
Clastic Sedimentary Rock (Composition: primarily Quartz, Clay minerals, and Hematite Fe2O3)
Sandstone (with potential Arkose/Lithic characteristics)
Arenite (Sedimentary rock composed of sand-sized grains)
Limestone
Limestone (Calcium Carbonate, CaCO3)
Bituminous Coal (with Anthracite or Vitrinite inclusion)
Organic-rich Sedimentary Rock (Carboniferous classification)
Granite
Phaneritic Igneous Rock (Granoid)
Greywacke
Lithic wacke (variety of Sandstone)
Limestone
Calcium Carbonate (CaCO3)
Sandstone
Arenite (SiO2 based)
Sandstone (Quartzose Sandstone)
Clastic Sedimentary Rock (primarily SiO2)
Sandstone
Arenite (primarily SiO2)
Quartzite / Sandstone / Chert Mix
Silicon Dioxide (SiO2)
Coquina
Biogenic Limestone (CaCO3)
Sandstone (likely Quartzose)
Sandstone (Principally SiO2)
Sandstone (Ferruginous)
Arenite with Iron Oxides
Sandstone (Quartzose)
Arenite (primarily SiO2)
Chert (River Pebble)
Microcrystalline quartz (SiO2)
Glauconitic Sandstone (or Greensand)
Glauconitic Siliciclastic Rock (Containing (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2)
Chert Pebble
Microcrystalline or cryptocrystalline Quartz (SiO2)
Sandstone (Ferruginous)
Arenite (composed primarily of SiO2 with Fe2O3 staining)
Sandstone (likely Calcareous or Micaceous)
Clastic sedimentary rock (primarily Quartz with Cementing Agents)
Sandstone
Clastic sedimentary rock (primarily SiO2)
Sandstone (Graywacke type)
Clastic Sedimentary Rock (Lithic Sandstone)
Red Sandstone
Arenite (with Iron Oxide / Hematite cementation)