Fossil

Probable fossil-bearing rock or mineral concretion

Unidentified carbonate-rich concretion with a possible fossil inclusion

Likely fossil oyster shell

Fossilized bivalve shell; exact species cannot be identified from the image

Crinoid Stem Fossil in Matrix

Phylum Echinodermata, Class Crinoidea

Fossiliferous limestone (likely a crinoidal or shell-fragment limestone)

Bioclastic limestone, composed chiefly of calcite (CaCO₃)

Fossil oyster shell

Oyster (family Ostreidae); shell composed chiefly of calcite (CaCO₃)

Rounded sedimentary pebble

Likely micritic limestone or calcareous sandstone

Chert with Fossil Brachiopod

Microcrystalline Quartz (SiO2) with Calcitic Brachiopod inclusion

Fossiliferous limestone

Bioclastic carbonate rock; predominantly calcite (CaCO₃), with fossil shell fragments

Sedimentary Outcrop (Sandstone/Shale)

Sedimentary bedrock formation (variable composition)

Fossil coral (likely a weathered colonial coral fragment)

Fossilized scleractinian coral; genus and age cannot be determined from the image

Fossiliferous limestone, possibly coral-bearing

Calcitic limestone (mostly CaCO₃; fossil fragments may include ancient colonial coral or shell material)

Possible fossilized bone fragment

Indeterminate fossil bone; no species can be identified from this image

Fossil in Shale

Fossiliferous Shale

Weathered limestone pebble

Calcite-rich limestone (primarily CaCO₃)

Weathered fossiliferous limestone

Calcitic limestone; predominantly calcium carbonate (CaCO₃), commonly containing fossil fragments

Crinoid Stem Fossils (Indian Beads / St. Cuthbert's Beads)

Crinoid columnal ossicles (phylum Echinodermata)

Fossiliferous Limestone or Shale

Biomicrite (if limestone) or Fossiliferous Shale

Fossiliferous limestone concretion

Calcite-rich limestone (primarily CaCO₃), possibly containing a fossil shell or coral fragment

Polished fossiliferous limestone, possibly coral or shell fossil

Calcite-rich limestone (CaCO₃), with probable fossilized skeletal structures

Weathered limestone pebble

Limestone, predominantly calcite (CaCO₃), possibly fossiliferous or oolitic

Weathered fossiliferous sandstone or mudstone cobble

Lithified siliciclastic sediment; the raised curved feature may be a trace fossil or shell impression

Weathered limestone or calcareous sandstone

Calcite-rich carbonate rock, chiefly calcium carbonate (CaCO₃), possibly fossiliferous limestone

Likely vertebra fossil or bone fragment

Indeterminate fossilized vertebra; mineralized hydroxyapatite, commonly Ca₅(PO₄)₃(OH)

Fossilized Crinoid Stem in Limestone

Crinoidea (Class) in Calcium Carbonate (CaCO3) matrix

Fossiliferous Limestone

Limestone with embedded fossil cross-section

Fossilized Shark Tooth (Partial) or Coprolite

Elasmobranchii (fossil) or Coprolite (trace fossil)

Fossil Shark Tooth

Carcharodon or Carcharias fossil (Vertebrate Fossil)

Tumbled fossiliferous limestone

Crinoidal limestone, chiefly calcite (CaCO₃), with fossil echinoderm fragments

Small fossilized tooth, possibly a shark tooth

Indeterminate fossil tooth; species cannot be identified from this image

Fossiliferous limestone

Bioclastic carbonate rock, predominantly calcite (CaCO₃)

Fossiliferous limestone with colonial coral fossils

Calcitic limestone; probable fossil tabulate or rugose coral (Class Anthozoa)

Fossiliferous Limestone (or Bryozoan/Coral Fossil Pebble)

Biogenic Sedimentary Rock (Calcium Carbonate, CaCO3)

Fossiliferous Limestone with Crinoid stems

Limestone (CaCO3) containing Crinoidea fossils

Crinoid Fossil in Limestone

Crinoidea fossil (stalk segments) in Calcium Carbonate (CaCO3) matrix

Fossiliferous limestone

Bioclastic limestone, commonly crinoidal or shelly limestone (calcite, CaCO₃)

Polished fossiliferous agate

Chalcedony (microcrystalline SiO₂) containing fossil fragments, likely an agatized limestone or stromatolite

Fossiliferous Limestone

Fossiliferous Calcilutite / Biomicrite

Fossil-bearing limestone or calcareous mudstone pebble

Micritic limestone, primarily calcite (CaCO₃), with possible fossil or iron-oxide vein features

Fossiliferous limestone pebble

Calcite-rich limestone, CaCO₃, with possible fossil or shell fragments

Fossil brachiopod shell

Brachiopoda; likely a ribbed strophomenid or productid brachiopod

Possible fossilized bone fragment

Fossil bone, composition primarily carbonate-hydroxylapatite [Ca₅(PO₄)₃(OH)]

Rounded fossil fragment, possibly fossiliferous limestone

Unidentified carbonate fossil or fossil-bearing limestone; exact fossil cannot be determined from the photograph