Sedimentary (Fossiliferous)

Likely weathered chert or siliceous shale

Cryptocrystalline quartz (SiO₂), possibly with clay minerals

Crinoid Fossil in Limestone

Crinoidea (Phylum Echinodermata) in Calcite Matrix (CaCO3)

Calamites Fossill (Lepidodendrales)

Calamites sp. (Family Calamitaceae)

Fossilized Shark Tooth

Elasmobranchii (various species, possibly Carcharias or Odontaspis)

Calcite-rich limestone, possibly fossiliferous

Limestone composed mainly of calcite (CaCO₃), potentially containing a fragmentary fossil or calcite-filled structure

Fossilized Shark Tooth

Chondrichthyes (Class)

Fossil-bearing limestone slab

Bioclastic limestone, likely containing brachiopod or bivalve impressions

Weathered limestone or calcitic fossil fragment

Calcite-rich carbonate rock; primarily CaCO₃

Silicified fossil-bearing limestone (likely chert/agate replacement)

Microcrystalline quartz (SiO₂) replacing carbonate rock; possible fossiliferous limestone

Orthoceras Fossil in Limestone

Orthoceras (extinct genus of cephalopods), mineralized as Calcite (CaCO3) in Fossiliferous Limestone

Ammonite Fossil

Ammonoidea (primarily composed of Calcite, CaCO3)

Fossil-bearing sedimentary rock, possibly fossil wood or bone

Indeterminate silicified/carbonate fossil in sandstone or mudstone

Fossiliferous Shale or Slate with Plant Fossils

Fossil-bearing argillaceous rock

Small shell fragment (likely gastropod or bivalve fossil)

Fossilized calcium-carbonate shell; chiefly aragonite or calcite (CaCO₃)

Limestone with Fossil Fish Fragment

Calcite (CaCO3) containing a fossil teleost

Calamites fossil

Calamites (extinct genus of arborescent horsetails)

Fossilized shell fragment in limestone

Bioclast (likely bivalve or brachiopod) preserved in calcitic limestone

Fossilized Bone

Vertebrate Fossil Fragment (Calcium Phosphate / Hydroxyapatite)

Dinosaur Fossil (Skull)

Dinosauria fossilis (Petrified Hydroxyapatite / Calcium Carbonate)

Weathered limestone fragment, possibly fossiliferous

Calcite-rich limestone (CaCO₃); exact identification is uncertain from one image

Slate with Fossiliferous Impressions

Metamorphosed Argillaceous Rock (Fossiliferous Slate)

Likely weathered limestone fragment

Limestone, composed mainly of calcite (CaCO₃)

Fossil-bearing limestone

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

Weathered limestone or calcareous concretion

Predominantly calcite (CaCO₃), possibly a fossil-rich limestone fragment

Sulfur-bearing Limestone (Solfatara Specimen)

Sulfur-rich Bio-limestone (Calcium Carbonate with Native Sulfur, S8)

Crinoid Stem Fragment

Crinoid (Phylum Echinodermata, Class Crinoidea)

Crinoid Columnal Fossil

Crinoid ossicle (Class Crinoidea)

Crinoid Stem Fossil

Class Crinoidea (Phylum Echinodermata), primarily Calcium Carbonate (CaCO3)

Crinoid Fossil Stem Segment

Class Crinoidea (Echinodermata)

Crinoid Columnal Fossil

Class Crinoidea (Echinodermata); usually calcite replacement (CaCO3)

Ammonite Fossil (Polished Section)

Ammonoidea (typically mineralized with Calcite CaCO3)

Weathered limestone (probable fossiliferous limestone)

Calcite-rich carbonate rock; predominantly calcium carbonate, CaCO₃

Limestone (specifically fossiliferous/skeletal limestone)

Calcium Carbonate (CaCO3)

Fossil Shark Tooth Fragment

Elasmobranchii dentition (fragment)

Fossil scallop shell

Bivalve mollusk shell, likely family Pectinidae; primarily calcite (CaCO₃)

Fossilized bivalve shell

Molluscan bivalve fossil; shell originally composed of calcium carbonate (aragonite/calcite, CaCO₃)

Fossilized Echinoid Fragment (Calycinal/Boss Fossil)

Echinodermata fossil fragment

Crinoid Fossil Fragment

Crinoidea (echinoderm fossil embedded in limestone/matrix)

Polished fossiliferous limestone

Fossiliferous micrite/bioclastic limestone, likely crinoidal or shell-rich limestone

Fossiliferous Limestone Pebble

Calcite-rich Fossiliferous Marine Limestone

Fossiliferous Jasper / Miriam Stone / Elephant Skin Jasper

Biogenic Chalcedony / Silicified Fossiliferous Limestone

Fossil ammonite

Ammonoidea; likely a chambered ammonite mold/cast