Sandstone
Arenite (primarily Quartz Arenite)
Category
Browse sedimentary (fossil) specimens identified by the Rock Identifier community.
Sandstone
Arenite (primarily Quartz Arenite)
Petrified Wood
Silicified wood (primarily SiO2)
Fossiliferous limestone
Calcite-rich limestone (CaCO₃), containing possible fossil or peloidal inclusions
Limestone
Calcium carbonate (CaCO3)
Limestone
Calcium Carbonate (CaCO3)
Shale (or Mudstone)
Siltstone/Argillite (composed mainly of clay and silt-sized particles)
Weathered limestone
Calcite-rich carbonate rock (mostly CaCO₃)
Limestone
Sedimentary Calcium Carbonate (CaCO3)
Limestone
Calcium Carbonate (CaCO3)
Shale (with Iron Staining)
Argillaceous mudstone / Shale
Sandstone
Arenite
Petrified Wood
Silicified Wood (SiO2)
Fossil Coral / Crinoid Stem section
Anthozoa / Crinoidea fossil
Quartz Geode Fragment
Silicon Dioxide (SiO2)
Geode (unopened)
Chert / Chalcedony Geode (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Limestone
Calcium Carbonate (CaCO3)
Quartz Geode
Silicon Dioxide (SiO2)
Limestone with Quartz/Calcite Veins
Sedimentary Limestone (CaCO3 with SiO2 or CaCO3 intrusions)
Sandstone
Arenite
Dendritic Limestone
Calcite with Manganese Oxide (Manganese Dendrites)
Sandstone
Arenite (primarily composed of SiO2)
Crinaudite / Fossilized Crinoid Stem
Crinoid (Echinodermata) in a Calcitic/Siliceous Matrix
Coal
Anthracite or Bituminous Coal
Limestone
Sedimentary Calcium Carbonate (CaCO3)
Limestone
Sedimentary Calcium Carbonate (CaCO3)
Sandstone (likely with Borings or Vesicular Basalt)
Clastic Sedimentary Rock (Sandstone)
Petrified Wood
Silicified Wood (primarily SiO2)
Dinosaur Bone (Gembone)
Silicified Dinosaur Bone (SiO2 replacing organic tissue)
Sandstone
Arenite (SiO2 primarily)
Limestone (River Pebble)
Sedimentary Calcium Carbonate (CaCO3)
Ammonite Fossil in Limestone Matrix
Ammonoidea (subclass) in Calcium Carbonate (CaCO3)
Septarian Nodule
Septarian Concretion (Calcite, Aragonite, and Limestone)
Fossiliferous Limestone (Red Marble)
Bioclastic Limestone (CaCO3)
Limestone
Calcareous sedimentary rock (CaCO3)
Limestone
Calcareous sedimentary rock (CaCO3)
Limestone (specifically Travertine or Tufa)
Calcium Carbonate (CaCO3)
Bituminous coal
Coal; predominantly vitrinite and inertinite macerals composed chiefly of carbon, hydrogen, oxygen, nitrogen, and sulfur
Weathered sandstone or arkose fragment
Quartz-rich clastic sedimentary rock; likely sandstone/arkose (dominantly SiO₂ quartz with feldspar and lithic grains)
Red Sandstone
Arenite (Ferruginous Sandstone)
Chert (Nodule)
Chert (mainly Microcrystalline or Cryptocrystalline Quartz, SiO2)
Fossiliferous Limestone (Coquina)
Biogenic Limestone (Calcium Carbonate, CaCO3)