Pearl
Aragonite (CaCO3 with conchiolin)
mineral
Category
Biogenic Material
Browse biogenic material specimens identified by the Rock Identifier community.
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Chert (Flint / Jasper)
Microcrystalline Quartz (SiO2)
sedimentary
Fossiliferous Limestone (with Crinoids/Coral)
Fossiliferous Limestone (CaCO3)
sedimentary
Chert (and Fossiliferous Limestone)
Silicon Dioxide (SiO2) within Calcium Carbonate (CaCO3)
sedimentary
Fossiliferous Limestone
Fossiliferous Calcarenite (CaCO3)
sedimentary
Fossiliferous Limestone
Fossiliferous Calcite (CaCO3)
sedimentary
Spiny Oyster Shell
Spondylus varians (Biogenic Calcium Carbonate)
mineral
Stromatolite
Biogenic sedimentary rock / Stromatolite
sedimentary
Fossiliferous Limestone
Biogenic Sedimentary Rock (CaCO3)
sedimentary
Stromatolite
Biogenic sedimentary rock / Stromatolite
sedimentary
Carbonate Beach Sand
Biogenic Carbonate Sediment (CaCO3)
sedimentary
Pearl
Biogenic CaCO3 (Aragonite and Calcite)
mineral
Fossiliferous Limestone
Biogenic Calcium Carbonate (CaCO3)
sedimentary
Pearl
Calcium Carbonate (CaCO3) with Conchiolin
mineral
Seashell (Cockle Shell)
Cardiidae (Bivalvia), primary composition: Calcium Carbonate (CaCO3) in the form of aragonite or calcite
fossil
Vesicular Limestone with Borings
Fossiliferous Calcarenite (Calcium Carbonate, CaCO3)
sedimentary
Red Coral (with Hematite and Black Pearl accents)
Corallium rubrum (Calcium Carbonate, CaCO3)
mineral
Fossiliferous Limestone with Crinoid stems
Calcite-rich Biogenic Sedimentary Rock (CaCO3)
sedimentary
Fossiliferous Limestone
Limestone with fossil inclusions (CaCO3)
sedimentary
Pearl (as a biogenic mineral/gemstone)
Calcium Carbonate (mostly Aragonite), CaCO3
mineral
Pearl
Calcium Carbonate (CaCO3) in the form of Aragonite
mineral
Fossiliferous Limestone
Carbonate sedimentary rock with trace fossils (CaCO3)
sedimentary
Fossiliferous Limestone (Coquina)
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Coal (Bituminous or Anthracite)
Organogenic Sedimentary Rock (Carbon)
sedimentary
Fossiliferous Limestone
Fossiliferous Limestone (CaCO3)
sedimentary
Fossiliferous Limestone
Bioclastic Limestone (CaCO3)
sedimentary
Fossil Shell in Sedimentary Matrix
Bivalvia (fossil) in Calcium Carbonate Matrix
sedimentary
Pearl
Organic Mineraloid (CaCO3 + Conchiolin)
mineral
Pearl
Aragonite and Conchiolin (CaCO3 + organic protein)
mineraloid
Banded Chert Pebble
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Kidney Stone (Calcium Oxalate / Uric Acid)
Calcium Oxalate Monohydrate (Whewellite) / Calcium Oxalate Dihydrate (Weddellite)
mineral
Chert (Smoky Variety)
Microcrystalline Quartz (SiO2)
sedimentary
Mother of Pearl (Nacre)
Aragonite (layered with organic polymers), CaCO3
mineral
Shiva Eye Shell (Operculum)
Calcium Carbonate (Aragonite), CaCO3
mineral
Oyster Shell Fragment
Crassostrea virginica (or related Bivalvia)
fossil
Natural Pearl
Calcium carbonate (primarily Aragonite and Conchiolin), CaCO3
mineral
Chert (Nodule)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
sedimentary
Goethite
Goethite (FeO(OH))
mineral
Ammolite
Ammolite (Biogenic Aragonite with trace elements; fossils of Placenticeras meeki and Placenticeras intercalare)
mineral
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Fossilized Shell in Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Freshwater Pearl
Calcium Carbonate (CaCO3) in the form of Aragonite and Calcite
gemstone