Fossil

Fossilized shell or coral fragment

Indeterminate biogenic carbonate; likely calcite/aragonite (CaCO₃)

Fossil-bearing concretion, possibly containing a fossil shell or other organic inclusion

Calcareous concretion; exact fossil and host-rock composition are not identifiable from the image

Bivalve Fossil (Fossilized Shell)

Class Bivalvia (fossilized in Calcium Carbonate/Aragonite)

Sandstone (likely Arkose or Quartz Sandstone)

Clastic sedimentary rock (primarily SiO2)

Limestone with Stylolites

Calcareous sedimentary rock (CaCO3)

Sandstone

Arenite (typically SiO2 + others)

Sandstone (Quartzose)

Arenite (Siliciclastic sedimentary rock)

Crinoid Stem Fossil

Crinoid ossicle / stalk segment (Phylum Echinodermata)

Fossil tooth, possibly shark tooth

Indeterminate fossilized vertebrate tooth; likely a shark tooth (possibly *Carcharhinus* or related genus)

Crinoid Fossil in Chert

Siliceous limestone with Crinoidea fossil (SiO2)

Weathered quartz-rich rock or fossil fragment

Indeterminate; likely quartz-bearing sandstone or siliceous fossil material

Fossiliferous Limestone with Quartz Veining

Limestone (Calcium Carbonate, CaCO3)

Fossiliferous Limestone

Biogenic Sedimentary Rock (Calcium Carbonate with Fossils)

Fossiliferous Limestone

Fossiliferous Limestone

Crinoidal Limestone

Bioclastic Limestone

Fossiliferous limestone pebble

Calcite-rich limestone containing possible brachiopod or coral fossil impressions

Fossiliferous Limestone Pebble

Calcite-rich Fossiliferous Marine Limestone

Limestone with Gastropod Fossil

Sedimentary Calcium Carbonate (CaCO3) with Gastropoda inclusion

Likely limestone or calcareous fossil fragment

Calcite-rich carbonate rock; possibly bioclastic limestone (CaCO₃)

Fossilized Shark Tooth (Fragment)

Elasmobranchii gen. et sp. indet. (Calcium Phosphate / Apatite fossil)

Petrified Wood

Silicified wood (Quartz/Chalcedony - SiO2)

Fossiliferous Limestone with Rugose Coral

Lithostrotionella (Limestone Matrix - CaCO3)

Tumbled fossiliferous limestone

Bioclastic limestone, likely crinoidal or shell-rich limestone (calcite, CaCO₃)

Limestone with Fossil Inclusion

Calcium Carbonate (CaCO3)

Fossil coral or stromatoporoid fragment

Likely fossilized colonial coral; exact taxon indeterminate from image

Fossiliferous Limestone / Coral Fossil

Fossiliferous Limestone with Anthozoa (Coral) fossil

Petrified Wood / Fossilized Bone

Silicified / Mineralized Fossil (Silica SiO2)

Fossiliferous Limestone

Calcium Carbonate (CaCO3) with marine fossils

Fossiliferous Flint

Microcrystalline Quartz (SiO2) with Echinoid Fossil

Likely polished/tumbled fossil shell or concretion

Indeterminate; possibly a fossil bivalve or gastropod in mineralized matrix

Coral Skeleton (Scleractinia)

Aragonite (CaCO3) biomineralisation within Anthozoa

Fossil-bearing limestone

Bioclastic limestone, chiefly calcite (CaCO₃), with embedded bivalve or brachiopod fossils

Sandstone concretion

Arenite sedimentary rock (concretion/nodule)

Fossiliferous Limestone

Biogenic Sedimentary Rock (Calcium Carbonate, CaCO3)

Likely fossiliferous limestone or dolostone

Micritic limestone, chiefly calcite (CaCO₃), possibly dolomitized; apparent fossil or stylolitic markings

Fossilized Shark Tooth

Chondrichthyes (Class)

Fossilized shell

Indeterminate bivalve shell; likely calcitic or aragonitic shell material (CaCO₃)

Fossiliferous limestone

Bioclastic limestone, chiefly calcite (CaCO₃), with fossil shell fragments

Knightia Fossil in Limestone

Knightia eocaena in micritic limestone

Fossiliferous shale or slate with plant impressions

Carbonaceous mudstone/shale; possible fossil plant material (often fern-like impressions)

Fossilized Shark Tooth

Elasmobranchii (fossilized matrix/root section)

Polished fossiliferous limestone, possibly ammonite-bearing

Calcite-rich limestone (CaCO₃), with fossil shell material