Siltstone
Siltstone (primarily SiO2 with Al2O3 and Fe2O3)
Category
Browse fossil specimens identified by the Rock Identifier community.
Siltstone
Siltstone (primarily SiO2 with Al2O3 and Fe2O3)
Fossilized Shark Tooth
Carcharodon carcharias (fossilized) / Hydroxyapatite permineralized with silica or iron
Fossilized Crinoid Stem
Class Crinoidea (Echinodermata)
Bituminous Coal
Organic Sedimentary Rock (composed mostly of carbon with sulfur and hydrogen)
Amber
Succinite (approximate formula C10H16O)
Fossiliferous Limestone (Coquina / Shell Limestone)
CaCO3 (Calcium Carbonate)
Sandstone (likely Graywacke or Lithic Sandstone)
Arenite / Wacke (SiO2 based with lithic fragments)
Sandstone (Weathered Pebble)
Arenite (primarily SiO2)
Chert Nodule
Chert (Cryptocrystalline variety of Quartz, SiO2)
Sandstone (with potential mineral inclusions)
Clastic sedimentary rock (primarily Quartz, SiO2)
Chert (White Chert)
Microcrystalline Quartz (SiO2)
Sandstone (with Manganese staining)
Arenite (composed primarily of SiO2)
Ferruginous Sandstone (Gritstone)
Clastic sedimentary rock with iron-rich cement (FeO(OH)·nH2O)
Chert (Nodule)
Silicon Dioxide (SiO2)
Chert (Nodule)
Silicon Dioxide (SiO2)
Limestone
Limestone (Calcium Carbonate - CaCO3)
Sandstone (Ferruginous)
Clastic sedimentary rock (primarily SiO2 with Fe2O3 cement)
Sandstone (Quartzose)
Arenite (primarily SiO2)
Limestone
Calcium Carbonate (CaCO3)
Sandstone
Arenite (SiO2 based)
Sandstone
Clastic sedimentary rock (primarily SiO2)
Limestone
Calcium Carbonate (CaCO3)
Sandstone (Quartzose Sandstone)
Arenite (primarily SiO2)
Sandstone (clastic)
Clastic Sedimentary Rock (primarily composed of SiO2)
Siltstone
Siltstone (composed of microscopic silt-sized particles of quartz and feldspar)
River Cobble (Conglomerate context)
Unconsolidated Fluvial Alluvium (comprised of various lithologies like Quartzite, Granite, or Basalt)
Sandstone (with cross-bedding)
Arenite (composed primarily of Quartz: SiO2)
Limestone (specifically fossiliferous/skeletal limestone)
Calcium Carbonate (CaCO3)
Chert (Chert Nodule)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Slate
Slate (Foliated Metamorphic Rock)
Sandstone (with manganese staining)
Clastic sedimentary rock (primarily SiO2)
Chalcedony (specifically Agate or Common Opal variety)
Cryptocrystalline Silica (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
Vesicular Sandstone
Clastic Sedimentary Rock (Sandstone)
Sandstone (with potential trace fossils)
Clastic sedimentary rock (primarily SiO2)
Red Sandstone (Iron-rich Sandstone)
Clastic Sedimentary Rock - Quartz Arenite / Arkose with Hematite Cement
Basalt
Basalt (Mafic Extrusive Igneous Rock)
Limestone
Calcium Carbonate (CaCO3)
Ferruginous Sandstone (Ironstone)
Arenite with Iron-Oxide Cement (FeO(OH)·nH2O / Fe2O3)
Limestone
Calcium Carbonate (CaCO3)