Fossil

Fossiliferous Limestone

Biogenic Limestone (Calcium Carbonate, CaCO3)

Fossiliferous Chert (with Brachiopod or Mollusk fragments)

Silicon dioxide (SiO2) with Calcium Carbonate (CaCO3) inclusions

Rugose Coral Fossil

Order Rugosa

Chert Pebble (with fossil shell fragment)

Microcrystalline Quartz (SiO2) with Calcified Invertebrate Impression

Fossiliferous Limestone / Fossil Fragment

Calcium Carbonate Matrix with Biogenic Inclusions (CaCO3)

Orthoceras Fossil in Limestone

Orthoceras regulare (Class Cephalopoda)

Fossiliferous Limestone (Crinoid stem fossils)

Sedimentary Limestone with Crinoidea ossicles

Fossiliferous Limestone

Calcium carbonate (CaCO3) matrix with fossil inclusions

Fossil shark tooth, likely sand tiger shark

Fossilized selachian tooth; possibly *Carcharias* or *Striatolamia*

Fossil bivalve or brachiopod in sedimentary rock

Unidentified fossil shell impression; likely a ribbed bivalve or brachiopod preserved in shale/siltstone

Tumbled coral fragment (likely white calcitic coral)

Calcium carbonate, primarily aragonite or calcite (CaCO₃); exact coral genus cannot be determined from the image

Petrified Wood

Silicified Wood (SiO2)

Fossilized Shark Tooth (Basal Bone)

Otodus sp. (Mineralized Hydroxyapatite)

Fossiliferous Chert (Chert with Crinoid Stem Impression)

Chert (SiO2) with fossil Anthozoan or Crinoid columnals

Fossil Coral (Petoskey Stone / Favosites / Charlevoix Stone)

Hexagonaria percarinata / Favosites (Cnidaria)

Petoskey Stone

Hexagonaria percarinata (Fossilized colonial rugose coral)

Fossilized Limestone with Crinoid Stem

Carboniferous Limestone (containing Crinoidea ossicles)

Fossiliferous Limestone Pebble

Biogenic Sedimentary Rock (CaCO3)

Fossil coral (likely tabulate or colonial coral)

Fossilized colonial coral; exact genus indeterminate from the photograph

Polished granite countertop with fossil shell

Granite; shell likely a fossilized bivalve or gastropod

Fossilized bivalve shell fragment

Fossil mollusk shell, likely a pectinid or related bivalve; original shell composed mainly of aragonite or calcite, now partly mineralized

Petoskey Stone (Fossilized Rugose Coral)

Hexagonaria percarinata

Fossiliferous Limestone

Carbonate sedimentary rock (CaCO3) with bioclasts

Crinoidean Fossil (Stem Fragment)

Phylum Echinodermata, Class Crinoidea

Crinoid Stem Segment Fossil

Crinoidea (columnal ossicle)

Fossil shark teeth

Likely fossilized shark teeth; exact species indeterminate from the image, possibly Carcharhiniformes or related taxa

Fossilized bivalve shell

Bivalvia (likely a venerid or similar clam); shell composed mainly of CaCO₃ as aragonite/calcite

Fossil Coral and Quartz Pebble

Fossilized Anthozoa / Silicon Dioxide (Quartz)

Weathered limestone slab

Micritic limestone, primarily calcite (CaCO₃)

Fossiliferous limestone

Bioclastic limestone, primarily calcite (CaCO₃), with possible shell or coral fossil molds

Stromatolite

Biogenic sedimentary structure (Stromatolite)

Crinoid Stem Fossil

Class Crinoidea (Echinodermata)

Polished fossilized ammonite or nautiloid shell

Ammonoidea or Nautiloidea; originally aragonitic shell, commonly replaced by calcite or chalcedony

Petrified Wood

Silicified Wood (SiO2)

Fossil Coral (Petoskey / Horn Coral Sliced Button)

Scleractinia / Rugosa (Silurian-Devonian Anthozoa)

Petrified Wood

Fossilized Wood (silicified wood)

Petrified Wood

Silicified Wood (SiO2)

Obsidian and Fossilized Shark Tooth

Obsidian (Volcanic Glass) and Otodus sp. (Fossilized shark tooth)

Petrified Wood

Silicified Wood (primarily Quartz/SiO2)

Amber

Succinite (C10H16O)

Fossilized Shark Tooth (Scapanorhynchus)

Scapanorhynchus texanus

Petoskey Stone

Hexagonaria percarinata (Fossilized Rugose Coral)