Organic (Geological Relative)

Petrified Wood

Silicified Wood (SiO2 permineralization)

Fossilized tooth, likely a mammalian tooth fragment

Indeterminate fossil tooth; possibly an ungulate or carnivoran tooth

Mixed Quartz and Jasper Pebbles

Silicon Dioxide (SiO2)

Travertine (Tufa)

Chemical Limestone (CaCO3)

Fossilized Echinoid (Sea Urchin)

Echinoidea (Class) - Often found as Micraster or Clypeaster specimens

Polished amber-like agate or jasper carving

Likely chalcedony (microcrystalline SiO₂), possibly iron-stained carnelian/jasper; exact identification requires testing

Chert Fossil (Pebble)

Microcrystalline Quartz (SiO2) with biogenic inclusions

Petrified Wood

Silicified wood (Quartz/Chalcedony replacement of cellulose)

Petrified Wood

Silicified wood (principally SiO2)

Petrified Wood

Silicified Wood (primarily SiO2)

Chert (and Petrified Wood)

Silicon Dioxide (SiO2)

Petoskey Stone

Hexagonaria percarinata (Calcite / CaCO3)

Pearl strand

Nacreous pearl, primarily aragonite (CaCO₃) with conchiolin protein

Honeycomb Coral Fossil

Favosites (extinct genus of tabulate coral)

Petrified Wood

Silicified Wood (primarily SiO2)

Pyrite

Pyrite (FeS2)

Polished fossiliferous limestone

Bioclastic limestone, commonly crinoidal or shell-rich micrite

Chert (Flint)

Chert (Cryptocrystalline variety of Quartz, SiO2)

Calcite-rich limestone or travertine

Calcite, CaCO₃; likely crystalline limestone/travertine with possible aragonite

Moss Agate

Silicon Dioxide (Chalcedony variety)

Petrified Wood

Silicified Wood (SiO2)

Limestone

Calcium Carbonate (CaCO3)

Petrified Wood

Silicified Wood (primarily SiO2)

Chert (variations include Flint or Jasper)

Silicon Dioxide (SiO2)

Fossil Coral (Petoskey / Horn Coral Sliced Button)

Scleractinia / Rugosa (Silurian-Devonian Anthozoa)

Chert (Jasper variation)

Chert (SiO2)

Chert Nodule

Chert (Microcrystalline Silicon Dioxide, SiO2)

Asphalt aggregate

Human-made bituminous asphalt containing crushed silicate rock aggregate

Honey calcite (orange calcite)

Calcite, calcium carbonate (CaCO₃)

Moss Agate and Hematite

Silica (SiO2) with fibrous inclusions of Manganese or Iron; Hematite (Fe2O3)

Petrified Wood

Silicified Wood (primarily SiO2)

Petrified Wood

Silicified Wood (primarily Chalcedony or Quartz, SiO2)

Fossiliferous Limestone

Sedimentary rock containing Indeterminate Fossil remains (likely Crinoid stem or Bryozoan fragment)

Fossiliferous Siltstone

Clastic Sedimentary Rock with Fossil Inclusions

Fossiliferous Limestone with Rugose Coral

Calcium Carbonate (CaCO3) featuring Rugosa (extinct order of solitary and colony corals)

Amber

Succinite (fossilized resin); C10H16O

Chert (Flint)

Microcrystalline Quartz (SiO2)

Lazulite

Lazulite (Mg,Fe2+)Al2(PO4)2(OH)2

Petrified Wood

Silicified Wood (primarily SiO2 - Silicon Dioxide)

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood (Silicified Wood)

Silicified Wood / Silicon Dioxide (SiO2)

Petrified Wood

Silicified Wood (primarily SiO2)