Fossil

Fossil coral (likely colonial/tabulate coral)

Fossilized scleractinian or tabulate coral; calcium carbonate, chiefly CaCO₃ (calcite/aragonite replaced by calcite)

Crinoid Stem Fossil in Chert

Crinoid columnal ossicles (phylum Echinodermata) embedded in microcrystalline quartz (chert)

Crinoid Stalk in Limestone

Crinoid fossil in Biomicrite (Limestone)

Fossiliferous Concretion

Septarian Concretion containing Brachiopods/Crinoids

Fossilized Bivalve Shell

Class Bivalvia (fossilized)

Fossilized Gastropod Internal Mold

Steinkern (Mollusca: Gastropoda)

Fossilized Shark Tooth (likely Sand Tiger Shark)

Carcharias taurus (fossilized hydroxyapatite/calcium phosphate)

Fossiliferous limestone

Bioclastic limestone, chiefly calcite (CaCO₃), with a visible fossil shell or fossil fragment

Fossilized coral or bryozoan limestone

Calcitic fossiliferous limestone; likely colonial coral/bryozoan fragments, CaCO₃

Fossilized bone fragment

Fossil bone, composed chiefly of carbonate-fluorapatite (bioapatite)

Fossil-bearing limestone

Bioclastic limestone, likely containing bivalve or brachiopod impressions

Fossiliferous shale or mudstone with plant fossils

Carbonaceous mudstone/shale containing fossilized foliage, likely fern or seed-fern impressions

Fossiliferous Limestone

Calcium carbonate matrix with macrofossils (CaCO3)

Fossiliferous limestone

Bioclastic carbonate rock, predominantly calcite (CaCO₃)

Fossil shark tooth

Likely fossilized shark tooth, possibly Carcharhinus or a related requiem shark

Fossiliferous limestone with a fossil sea urchin

Bioclastic limestone containing an echinoid fossil (class Echinoidea)

Sea Urchin Fossil

Echinoidea (test/fossil)

Polished fossiliferous agate (likely fossil coral or shell in silica)

Silicified fossil in chalcedony, a microcrystalline form of quartz (SiO₂); exact fossil type is uncertain from the image

Fossil gastropod shell

Gastropoda; species cannot be determined from the image

Fossiliferous limestone

Bioclastic carbonate rock, primarily calcite (CaCO₃)

Fossiliferous limestone with a possible shell or trace fossil

Calcitic limestone (mostly CaCO₃), fossil identity indeterminate from the image

Fossiliferous Sandstone Pebble (with Crinoid / Shell Impression)

Sandstone containing fossiliferous inclusions (SiO2 matrix with calcite/silica cast fossil)

Fossiliferous limestone, possibly a weathered shell or bone fragment

Calcite (CaCO₃) fossil material in limestone; exact fossil identification is uncertain from the image

Fossil coral

Likely colonial rugose coral (e.g., Lithostrotion or Hexagonaria), replaced by calcite

Fossilized honeycomb coral

Fossil coral, commonly Favosites or related tabulate coral

Fossil bivalve shell fragment

Likely a ribbed oyster or scallop-type bivalve; exact genus requires locality and preservation details

Fossiliferous limestone with silicified fossil material

Bioclastic limestone; likely marine mollusk/coral fragments, locally replaced by chalcedony or calcite

Fossiliferous limestone, likely with a coral or stromatoporoid fossil

Calcite (CaCO₃) limestone containing fossilized marine skeletal material

Polished fossil tooth, likely shark tooth

Fossilized selachian tooth; possible sand tiger shark (Carcharias sp.) or related lamniform

Possible fossilized tooth fragment

Indeterminate fossil enamel/dentine; possibly shark tooth fragment

Bivalve Fossil (Clam Fossil)

Class Bivalvia (likely Gryphaea or similar Order)

Silicified fossil shell, likely fossil oyster or clam

Silicified bivalve fossil; shell originally aragonite/calcite, partly replaced by chalcedony (SiO₂)

Fossil Shell

Invertebrate fossil (Mollusca)

Fossiliferous limestone

Bioclastic limestone, primarily calcite (CaCO₃)

Devil's Toenail (Fossil Oyster)

Gryphaea arcuata (Calcium Carbonate, CaCO3)

Fossiliferous Shale

Fossiliferous Mudstone / Shale

Fossiliferous limestone, likely coral or shell-rich limestone

Biogenic calcite (CaCO₃), commonly limestone containing fossil coral or mollusks

Fossiliferous limestone with a coiled gastropod fossil

Gastropod fossil preserved in calcitic limestone; the exact fossil taxon cannot be determined from the image

Fossiliferous Limestone

Calcium Carbonate (CaCO3) with Biogenic Fossils

Fossiliferous Limestone (Crinoidal)

Calcite-bearing bioclastic packstone (CaCO3)

Orthoceratid Fossil in Limestone

Orthoceras (extinct genus of Nautiloid Cephalopod)

Fossiliferous limestone (reef or shell-rich limestone)

Bioclastic calcarenite/calcirudite; predominantly calcite (CaCO₃)