Sedimentary (Fossiliferous)

Chert / Flint (Brecciated or Fossiliferous Limestone with Silicification)

Sedimentary cryptocrystalline quartz (SiO2)

Fossil coral or shell fragment

Indeterminate calcareous fossil; likely aragonite or calcite (CaCO₃)

Fossil-bearing limestone, possibly a crinoid or shell fragment

Calcite (CaCO₃) limestone containing an indeterminate marine fossil

Fossil coral limestone

Fossilized colonial coral, commonly tabulate or rugose coral, preserved in calcite (CaCO₃)

Mixed Quartz and River Pebbles (Stone Collection)

Mixed assortment containing mainly Silicon Dioxide (SiO2)

Small rounded limestone pebble

Micritic limestone, chiefly calcite (CaCO₃); possibly an oolitic or fossiliferous limestone fragment

Polished fossil-bearing limestone pebble

Bioclastic limestone, chiefly calcite (CaCO₃), possibly containing a small shell or coral fragment

Small weathered pebble, possibly limestone

Indeterminate carbonate-rich rock; likely calcite-bearing limestone

Belemnite Fossil (Guard)

Belemnoidea (Carbonate/Calcite replacement)

Crinoid Stem Fossil (in matrix)

Crinoid (Class Crinoidea)

Ammonite Fossil

Ammonoidea (primarily composed of Calcite, CaCO3, or Pyrite)

Crinoid Stem Fossil

Class Crinoidea (Phylum Echinodermata), often preserved in Limestone or Calcite (CaCO3)

Fossil Plant Impression (Calamites)

Calamites sp. (Tracheophyta: Equisetopsida)

Crinoid Stem Fossil

Crinoid columnal (Class Crinoidea)

Crinoidal Limestone

Bioclastic Limestone

Calamites (Fossil Plant)

Calamites (Genus), belonging to the class Equisetopsida

Crinoid Stem Fossil in Matrix

Crinoid (Class Crinoidea) in Limestone/Siltstone matrix

Crinoid Stem Fossil in Matrix

Phylum Echinodermata, Class Crinoidea

Fossiliferous limestone pebble

Bioclastic limestone, likely coral-rich (calcium carbonate, CaCO₃; commonly calcite)

Fossil oyster shell

Fossilized bivalve, likely Ostrea or Crassostrea; calcite (CaCO₃) shell

Porous fossil fragment (possibly fossilized coral or shell)

Unidentified fossil carbonate; likely calcite/aragonite

Small conical fossil shell fragment

Indeterminate gastropod or scaphopod shell; likely calcium carbonate (aragonite/calcite)

Crinoid fossil in limestone

Crinoidea fossil, commonly preserved in bioclastic calcitic limestone (CaCO₃)

Fossil-bearing bioclastic limestone

Bioclastic calcarenite/calcirudite, chiefly calcite (CaCO₃)

Fossiliferous Limestone / Fossil Fragment

Calcium Carbonate (CaCO3) with indeterminate biogenic remains

Weathered fossiliferous limestone

Calcitic limestone, primarily calcium carbonate (CaCO₃), possibly containing fossil fragments

Tumbled fossiliferous limestone

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

Fossiliferous Chert Nodule

SiO2 (Microcrystalline Quartz) with fossil inclusions

Weathered fossiliferous limestone

Calcite-rich limestone (CaCO₃), possibly containing fossil fragments or stylolites

Weathered limestone or calcitic marble

Calcite-rich carbonate rock, chiefly CaCO₃; likely fossiliferous limestone, possibly weakly metamorphosed marble

Fossil-bearing limestone

Bioclastic limestone, likely containing bivalve or brachiopod impressions

Fossiliferous Limestone (Crinoid stem fragments)

Bioclast-bearing Carbonate Rock (Caco3)

Fossil oyster shell fragment

Fossilized oyster (Ostreidae), composed mainly of calcite (CaCO₃)

Crinoid Stem Fossil

Crinoid ossicle (phylum Echinodermata)

Fossilized bivalve shell fragment

Calcitic shell material, commonly Arca or related marine bivalve; primarily CaCO₃

Layered shale and sandstone gorge

Shale and thin-bedded sandstone, likely Devonian or older sedimentary strata

Fossiliferous limestone pebble

Calcitic limestone, primarily CaCO₃ (calcite), containing a possible trace-fossil or shell fragment

Polished fossiliferous limestone

Bioclastic limestone, likely containing a solitary rugose coral or shell fossil (identification uncertain from image)

Polished fossiliferous agate

Chalcedony (microcrystalline SiO₂), likely fossil-bearing agate

Crinoid Stem Fossil

Crinoida (columnal ossicles)

Fossilized shell or brachiopod

Likely a calcareous brachiopod or bivalve fossil; exact identification requires clearer detail and scale

White coral limestone (probable fossiliferous limestone)

Calcite (CaCO₃), commonly derived from aragonitic coral skeletons recrystallized to calcite