Mineral Like Biological Tissue

Fossilized shell or coral fragment

Indeterminate biogenic carbonate; likely calcite/aragonite (CaCO₃)

Fossilized Shell in Limestone

Biogenic Limestone (Calcium Carbonate, CaCO3)

Fossilized shell fragment

Indeterminate fossil mollusk; likely a silicified or mineral-replaced bivalve/gastropod fragment

Amber

Succinite (Formula: C10H16O)

Fossil shell fragment

Indeterminate mollusk shell; likely gastropod or bivalve, composed mainly of calcium carbonate (aragonite/calcite)

Tumbled fossil coral or carbonate fossil fragment

Likely fossilized coral, composed mainly of calcite (CaCO₃); exact identification is uncertain from the image

Fossilized Shark Tooth

Chondrichthyes (Class) fossilized tooth

Coprolite

Coprolite (fossilized feces)

Likely weathered limestone or calcitic marble

Calcite (CaCO₃), probably micritic limestone; marble is a possible metamorphic alternative

Burmese Amber (Burmite)

Burmite (C10H16O)

Fossil Shark Tooth (Otodus obliquus)

Otodus obliquus; hydroxyapatite (mineralized form Ca5(PO4)3(OH))

Fossiliferous limestone, possibly containing a brachiopod or bivalve fossil

Calcite-rich limestone (CaCO₃), with an apparent shell impression or shell fragment

Pearl

Nacre (aragonite, CaCO₃, in a conchiolin matrix)

Shark Tooth Fossil

Vertebrate fossilized tooth (various genera such as Carcharodon, Otodus, or Negaprion)

Aragonite (Onyx Marble)

Aragonite / Calcium Carbonate (CaCO3)

Megalodon Shark Tooth

Otodus megalodon

Weathered granite or granitic gneiss boulder

Granite–gneiss; chiefly quartz, feldspar, and mica

Weathered granitic/concrete-looking boulder (likely granite or granodiorite)

Granite–granodiorite; chiefly quartz, feldspar, and mica

Calcite

Calcium Carbonate (CaCO3)

Banded limestone or marble

Calcite-rich carbonate rock; likely veined limestone, possibly low-grade marble (CaCO₃)

Weathered sandstone boulder

Sandstone, chiefly quartz (SiO₂) with feldspar and iron-oxide cement

Fossilized tooth, likely mammalian molar

Indeterminate Mammalia; mineralized dentine and enamel

Lichen-covered granite

Granite, chiefly quartz–feldspar–mica; surface colonized by lichens

Fossilized Shell in Limestone

Carbonate sedimentary rock with Bivalvia or Brachiopoda remains

Fossilized bone, likely a large vertebrate limb or rib fragment

Petrified bone; exact taxon indeterminate from the image

Fossilized shell fragment, likely bivalve

Bivalvia indet.; commonly preserved as calcite (CaCO₃) shell material

Crinozoan fossil (Crinoid stem fragment)

Crinoid (Class Crinoidea)

Limestone

Calcium Carbonate (CaCO3)

Bay Scallop Shell

Argopecten irradians (Biogenic Calcium Carbonate / CaCO3)

Tufa

Calcium carbonate (CaCO3) - Porous Limestone

Fossiliferous Limestone

Biogenic Limestone (CaCO3)

Fossiliferous Rock (Invertebrate Fossil in Matrix)

Fossiliferous limestone or shaly matrix containing skeletal fossil remains

Fossilized coral or stromatoporoid fragment

Likely tabulate coral (order Tabulata) or stromatoporoid; exact identification requires microscopy

Shark Tooth Fossil

Carcharhiniformes or Lamniformes (order level fossil)

Amber

Succinite (specifically for Baltic amber); Chemical formula approximately C10H16O

Amber

Succinite (fossilized resin, C10H16O)

Polished orbicular jasper

Orbicular jasper, an opaque microcrystalline quartz (SiO₂) aggregate with iron-oxide and other mineral inclusions

Pumice

Vesicular volcanic glass (primarily SiO2 with Al2O3)

Orange Tabby (Felis catus)

Felis silvestris catus (variety: Red Mackerel Tabby)

Weathered limestone pebble

Limestone, primarily calcite (CaCO₃)

Likely quartz-rich stone or shell fragment

Uncertain; possibly quartz (SiO₂) or a calcareous shell fragment (CaCO₃)

Aragonite cluster

Aragonite, CaCO₃ (orthorhombic polymorph of calcite)