Igneous And Fossil

Tumbled fossiliferous limestone

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

Fossil oyster shell

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

Fossiliferous limestone

Bioclastic carbonate rock, predominantly calcite (CaCO₃)

Fossiliferous limestone with colonial coral fossils

Calcitic limestone; probable fossil tabulate or rugose coral (Class Anthozoa)

Fossilized Shark Tooth (Partial) or Coprolite

Elasmobranchii (fossil) or Coprolite (trace fossil)

Fossil Shark Tooth

Carcharodon or Carcharias fossil (Vertebrate Fossil)

Fossil shell fragment, likely bivalve or gastropod

Fossilized calcium-carbonate shell; likely aragonite/calcite replaced by calcite

Fossiliferous Limestone (or Bryozoan/Coral Fossil Pebble)

Biogenic Sedimentary Rock (Calcium Carbonate, CaCO3)

Fossiliferous Limestone with Crinoid stems

Limestone (CaCO3) containing Crinoidea fossils

Crinoid Fossil in Limestone

Crinoidea fossil (stalk segments) in Calcium Carbonate (CaCO3) matrix

Polished fossiliferous agate

Chalcedony (microcrystalline SiO₂) containing fossil fragments, likely an agatized limestone or stromatolite

Oyster shell fragment

Ostreidae shell; primarily calcite (CaCO₃)

Pyrite

Iron Sulfide (FeS2)

Pyrite

Iron Disulfide (FeS2)

Chalcedony (Tumbled)

Silicon Dioxide (SiO2)

Vesicular basalt (weathered lava rock)

Basalt, predominantly plagioclase, pyroxene, and minor olivine/iron oxides

Vesicular volcanic rock, likely pumice or scoriaceous rhyolite

Vesicular rhyolite/dacite; predominantly silica-rich volcanic glass with feldspar and quartz

Fossiliferous Limestone

Fossiliferous Calcilutite / Biomicrite

Fossiliferous limestone, possibly a shell or bone fragment

Calcitic limestone; predominantly calcium carbonate (CaCO₃), likely calcite

Fossil-bearing limestone or calcareous mudstone pebble

Micritic limestone, primarily calcite (CaCO₃), with possible fossil or iron-oxide vein features

Pyrite (Fool's Gold)

Iron Disulfide (FeS2)

Fossil brachiopod shell

Brachiopoda; likely a ribbed strophomenid or productid brachiopod

Possible fossilized bone fragment

Fossil bone, composition primarily carbonate-hydroxylapatite [Ca₅(PO₄)₃(OH)]

Weathered fossil shell fragment

Likely a fossilized bivalve or gastropod fragment; exact taxon cannot be determined from one view

Polished fossiliferous limestone

Bioclastic limestone, commonly crinoidal or shell-rich micrite

Fossilized Shark Tooth

Chondrichthyes (Class) fossil

Fossiliferous Limestone

Biogenic Limestone with Brachiopod/Crinoid fragments

Weathered quartz-rich rock fragment

Indeterminate; likely quartz-bearing granitoid or quartzite

Pearl-bearing oyster shell

Nacreous shell, primarily aragonite (CaCO₃), with natural pearls (calcium-carbonate nacre)

Weathered vesicular basalt (probable volcanic bomb)

Basalt, primarily plagioclase feldspar, pyroxene, and olivine

Beach Pebble (Basalt / Greywacke Gravel)

Mafic Volcanic Rock (Basalt)

Tumbled black-and-white stone, likely dalmatian jasper

Quartz-rich porphyritic rhyolite (commercially called dalmatian jasper), with black aegirine/arfvedsonite-like inclusions

Shark Tooth Fossil

Chondrichthyes fossil

Fossil Snail

Gastropoda fossil

Fossil Snail Shell (Embedded in Resin)

Gastropoda fossil

Seashell Fossil

Gastropoda fossil

Pyrite (Fool's Gold)

Iron Sulfide (FeS2)

Weathered quartz-rich cobble, possibly quartzite or feldspar-rich granite

Quartz–feldspar aggregate; identification is uncertain from the photograph

Snowflake obsidian

Volcanic glass (obsidian), chiefly silica-rich rhyolitic composition, with cristobalite or feldspar spherulites

Fossil coral fragment

Likely fossilized colonial coral; exact taxon cannot be determined from the fragment

Fossiliferous limestone

Bioclastic limestone, predominantly calcite (CaCO₃)

Fossiliferous limestone pebble

Bioclastic limestone, primarily calcite (CaCO₃)