Organic Specimen (Fossil)

Petrified Wood

Silicified Wood (primarily SiO2 - Silicon Dioxide)

Fossiliferous limestone, possibly an oyster or other bivalve fossil

Calcite (CaCO₃) shell material preserved in micritic limestone; exact fossil taxon cannot be confirmed from one image

Spinosaurus Tooth Fossil

Spinosaurus aegyptiacus (Calcium Phosphate/Apatite)

Rugose Coral Fossil

Rugosa (Order)

Tooth or shell fragment (likely fossilized marine material)

Indeterminate; possibly a fossil fish tooth or mollusk shell fragment composed mainly of calcium carbonate (CaCO₃)

Amber

Succinite (Organic Mineraloid) - C10H16O

Petrified wood

Silicified wood, chiefly microcrystalline quartz (SiO₂)

Crinoid Stem Fragment

Crinoid (Phylum Echinodermata, Class Crinoidea)

Petrified Wood

Silicified wood (primarily SiO2)

Chert (specifically a flint nodule component)

Microcrystalline quartz (SiO2)

Fossil Shark Tooth

Carcharocles (Otodus) sp. or similar fossilized Chondrichthyes tooth

Kambaba Jasper

Rhyolite (with Stromatolite fossil inclusions)

Manganese-coated Sandstone

Clastic sedimentary rock with Manganese Oxide (often Pyrolusite or Psilomelane)

Sandstone Pebble

Arenite (primarily SiO2)

Agatized Dinosaur Bone

Permineralized Dinosaur Bone (Silicified/Agatized Bone)

Fossil-bearing limestone

Bioclastic limestone, likely containing a brachiopod or bivalve imprint

Amber

Succinite (with formula approximately C10H16O)

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

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

Petrified Wood

Silicified Wood (SiO2)

Weathered limestone

Calcite-rich limestone (CaCO₃), possibly fossiliferous or dolomitic

Crinoid Stem Fossil (Indian Bead)

Crinoid ossicle (Echinodermata)

Fossilized Insect in Nodular Matrix

Invertebrata / Insecta fossil in sedimentary concretion

Shark Tooth Fossil

Otodus obliquus (or similar prehistoric lamniform shark tooth)

Petrified Wood

Silicified wood (primarily quartz, SiO2)

Petoskey Stone

Hexagonaria percarinata (Calcite / CaCO3)

Sandstone

Arenite (primarily SiO2)

Brachiopod Fossil in Limestone

Phylum Brachiopoda (likely Order Spiriferida), CaCO3 (Calcite)

Chert (Yellow Jasper/Flint)

Silicon Dioxide (SiO2)

Petrified Wood

Silicified Wood (SiO2)

Sandstone

Arenite (SiO2 dominated sandstone)

Petrified Wood

Silicified Wood (primarily SiO2)

Shale

Fissile mudstone (primarily clay minerals and silt-sized quartz)

Coral Fossil

Anthozoa (Scleractinia)

Fossiliferous Limestone

Biogenic Limestone (Calcium Carbonate, CaCO3)

Fossiliferous Limestone

Biogenic Limestone (Calcium Carbonate, CaCO3)

Sandstone (Ferruginous)

Clastic Sedimentary Rock (SiO2 with FeO/Fe2O3)

Fossiliferous Mudstone / River Pebble

Sedimentary rock with trace fossil or inclusion

Shale

Laminated Fissile Pelite

Limestone (River Pebble / Fossiliferous Limestone)

Calcium Carbonate (CaCO3)

Baltic Amber (Black)

Succinite (Fossilized Tree Resin)

Fossils in Limestone (Crinoid / Marine Invertebrate Fossil)

Fossiliferous Limestone (containing Crinoidea / Brachiopoda)

Likely limestone or calcareous fossil fragment

Calcite-rich carbonate rock; possibly bioclastic limestone (CaCO₃)