Sandstone (Weathered Cobble)
Clastic Sedimentary Rock (primarily SiO2)
sedimentary
Category
Organic Specimen (Fossil)
Browse organic specimen (fossil) specimens identified by the Rock Identifier community.
Sandstone (Flagstone)
Arenite (composed primarily of SiO2)
sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary
Chert Pebble
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Fossil Coral
Coral Limestone (a type of biogenic sedimentary rock)
Sedimentary
Amber
Succinite (C10H16O)
mineraloid
Fossiliferous Limestone (Chertified Limestone)
Calcium Carbonate (CaCO3) often replaced by Microcrystalline Silica (SiO2)
sedimentary
Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Amber
Succinite (specific to Baltic amber), fossilized tree resin
mineraloid
Coquina
Biogenic Limestone (Calcium Carbonate - CaCO3)
sedimentary
River Stone (likely Mudstone or Siltstone)
Lutite (Clastic sedimentary rock composed of clay and silt-sized particles)
sedimentary
Sandstone (Ferruginous)
Arenite (with Goethite/Limonite cement)
sedimentary
Banded Chert
Microcrystalline Quartz (SiO2)
sedimentary
Sandstone (likely Quartzose Sandstone pebble)
Arenite (primarily SiO2)
sedimentary
Sandstone (likely Graywacke or Arkose variant)
Clastic Sedimentary Rock (SiO2 with assorted lithic fragments)
sedimentary
Sandstone
Arenite (primarily composed of SiO2)
sedimentary
Banded Chert
Microcrystalline Quartz (SiO2)
sedimentary
Petrified Wood (Calamites Fossil)
Calamites sp. (Silicified/Permineralized Plant Fossil)
sedimentary
Amber
Succinite (Fossilized Resin C10H16O)
Organic Mineraloid
Petrified Wood
Silicified Wood (primarily SiO2)
sedimentary
Sandstone
Arenite (composed primarily of SiO2)
sedimentary
Coral Rock (Coquina)
Biogenic Limestone (Calcium Carbonate - CaCO3)
sedimentary
Stromatolite
Biogenic Sedimentary Rock (composed predominantly of CaCO3)
sedimentary
Fossilized Coral
Cnidaria (Anthozoa), often replaced by Calcium Carbonate (CaCO3) or Silica (SiO2)
sedimentary
Petoskey Stone
Hexagonaria percarinata (Fossilized Rugose Coral)
sedimentary (fossilized)
Sandstone (Stream-rounded)
Arenite (SiO2 based)
sedimentary
Coal (specifically Bituminous or Anthracite)
Organic sedimentary rock; primarily Carbon (C) with varying H, S, O, N
sedimentary
Chert (specifically Gray/Blue Chert)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Sandstone (likely Fossilized Wood or Concrete Simulacrum)
Arenite / Silicified Wood / Anthropogenic Concrete
sedimentary
Chert (specifically Tan/Yellow Chert)
Silicon Dioxide (SiO2)
sedimentary
Fossilized Bone Fragment
Permineralized Vertebrate Fossil (Hydroxyapatite replaced by Minerals)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Fossilized Shark Tooth (Cretaceous to Neogene)
Elasmobranchii dental fossil (likely Squalicorax or similar species)
mineral (biogenic replacement)
Shale
Fissile mudrock (composed primarily of clay minerals and quartz)
sedimentary
Sandstone (Weathered)
Arenite (primarily SiO2)
sedimentary
Ironstone Concretion (Boji Stone/Moqui Marble type)
Goethite/Hematite-encrusted Sandstone Concretion
sedimentary
Chert (Chert Nodule with Cortex)
Microcrystalline Quartz (SiO2)
sedimentary
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Fe2O3 staining)
sedimentary
Fossiliferous Limestone (Coquina / Shell Limestone)
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Bituminous Coal
Bituminous coal (Organic Sedimentary Rock)
sedimentary
Glauconitic Sandstone (Greensand)
Glauconitic quartz wacke or arenite
sedimentary
Fossiliferous Chert with Brachiopod Impression
Chert (SiO2) containing Brachiopoda fossil remains
sedimentary