Fossil Shark Tooth
Otodus sp. (possibly Otodus obliquus)
fossil
Category
Mineral (Biogenic)
Browse mineral (biogenic) specimens identified by the Rock Identifier community.
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Pearl
Aragonite / Calcium Carbonate (CaCO3)
mineral
Pearl
Aragonite and Calcite (CaCO3) with Conchiolin
mineral
Calcite
Calcium Carbonate (CaCO3)
mineral
Pearl
Calcium Carbonate (primarily Aragonite and Calcite), CaCO3
mineral
Tahitian Pearl (Black / Pistachio Pearl)
Biogenic Aragonite / Calcite (CaCO3 with conchiolin)
gemstone
Mother of Pearl (Nacre)
Calcium Carbonate (Aragonite) with organic conchiolin
gemstone
Chert (Jasper / Iron-stained Chert)
Microcrystalline Quartz (SiO2 with Fe-oxides)
sedimentary
Chert
Chert (SiO2)
sedimentary
Possible fossilized shell or coral fragment
Indeterminate biogenic carbonate, likely calcite (CaCO₃)
fossil
Chert (Nodule)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
sedimentary
Nacre (Mother of Pearl)
Nacre (Biogenic Aragonite/Calcite composite, CaCO3)
mineral
Stromatolite
Biogenic sedimentary rock / Stromatolite
sedimentary
Carbonate Beach Sand
Biogenic Carbonate Sediment (CaCO3)
sedimentary
Stromatolite
Biogenic sedimentary rock / Stromatolite
sedimentary
Fossiliferous Limestone
Biogenic Sedimentary Rock (CaCO3)
sedimentary
Coquina or Coral Fossil
Biogenic Limestone (Calcite/Aragonite)
sedimentary
Coquina
Biogenic Limestone (Calcite, CaCO3)
sedimentary
Coquina
Biogenic Limestone (Calcite, CaCO3)
sedimentary
Fossiliferous Limestone
Biogenic Calcium Carbonate (CaCO3)
sedimentary
Coquina
Biogenic Limestone (Calcite / CaCO3)
sedimentary
Coquina (Limestone)
Bioclastic Limestone (CaCO3)
sedimentary
Fossilized Shell Fragment / Mother of Pearl
Calcium Carbonate (CaCO3) - Aragonite/Calcite biomineral
fossil
Black Pearl (Tahitian-style Cultured Pearl)
Calcium Carbonate (Aragonite) with Conchiolin (CaCO3)
mineral
Atlantic Calico Scallop (Biogenic Aragonite/Calcite)
Argopecten gibbus (Chemical: CaCO3)
mineral
Chert (Flint)
Microcrystalline Quartz (SiO2)
sedimentary
Chert Pebble with Quartz Veining
Microcrystalline Quartz (SiO2)
sedimentary
Mother of Pearl (Nacre)
Nacre (Aragonite/Conchiolin), CaCO3 + Organic Polymers
mineral
Banded Chert
Microcrystalline Quartz (SiO2)
sedimentary
Pearl (Pendant)
Calcium Carbonate (Aragonite/Calcite) - CaCO3
gemstone
Chert (Flint)
Microcrystalline Quartz (SiO2)
sedimentary
Oyster Shell (Aragonite/Calcite)
Calcium Carbonate (CaCO3)
sedimentary
Pearl
Calcium carbonate (principally Aragonite, CaCO3) with Conchiolin
gemstone
Mookaite Jasper
SiO2
Sedimentary
Pearl
Biogenic Calcium Carbonate (Aragonite and Conchiolin), CaCO3
mineral
Tahitian Pearl
Biogenic Calcium Carbonate (Aragonite/Calcite), CaCO3
mineral
Black Freshwater Pearls
Biogenic Calcium Carbonate (Aragonite/Calcite), CaCO3
mineral
Coquina
Biogenic Limestone (Calcitic shells)
sedimentary
Fossiliferous Limestone with Brachiopod
Phylum Brachiopoda in calcitic matrix
sedimentary
Limestone (Elephant Skin or Karst-weathered)
Calcium Carbonate (CaCO3)
sedimentary
Limestone (River Stone)
Calcium Carbonate (CaCO3)
sedimentary
Fossiliferous Chert (Gryphaea Fossil)
Silicon Dioxide (SiO2) with Calcitic Mollusk Remnants
sedimentary