Jasper (or Chert)
Microcrystalline Quartz (SiO2)
sedimentary
Category
Biogenic Material
Browse biogenic material specimens identified by the Rock Identifier community.
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Mixed Gemstone Collection
SiO2 (Quartz varieties) and Biogenic CaCO3 (Nacre)
mineral
Fighting Conch (Sea Shell)
Strombus alatus (primarily composed of Calcium Carbonate / CaCO3)
mineral
Pearl (likely Freshwater or Akoya Cultured)
Aragonite / Conchiolin composite (CaCO3)
Mineralloid (Organic gemstone)
Pearl
Calcium Carbonate (CaCO3)
mineral
Chalky limestone
Micritic limestone, predominantly calcite (CaCO₃)
sedimentary
Fossiliferous Limestone with Brachiopod
Phylum Brachiopoda in Sedimentary Matrix (CaCO3)
fossil
Coquina / Fossiliferous Limestone
Fossiliferous Limestone / CaCO3
sedimentary
Fossiliferous Limestone
Limestone (Calcium Carbonate, CaCO3)
sedimentary
Pearl (as a biogenic mineral/gemstone)
Calcium Carbonate (mostly Aragonite), CaCO3
mineral
Polished chert or jasper pebble
Microcrystalline quartz (SiO₂), likely chalcedony-rich chert/jasper
sedimentary
Sea Shell Fragment (Calcium Carbonate)
Aragonite / Calcite (CaCO3)
fossil
Pearl oyster shell with cultured pearls
Mollusk shell (likely Pinctada spp.) containing aragonite pearls, CaCO₃
gemstone
Fossiliferous Limestone (Coquina)
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Fossilized Shell in Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
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
Coal (Bituminous or Anthracite)
Organogenic Sedimentary Rock (Carbon)
sedimentary
Fossiliferous Limestone
Carbonate sedimentary rock with trace fossils (CaCO3)
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
Wampum / Quahog Shell Fossil Fragment
Mercenaria mercenaria (Calcium carbonate, CaCO3)
fossil
Chert (or Petrifed Wood / Banded Flint)
Silicon Dioxide (SiO2)
sedimentary
Black Pearl (Tahitian Style)
Calcium Carbonate (Aragonite) - CaCO3 with Conchiolin
mineral
Fossiliferous Limestone
Calcium Carbonate (CaCO3) with Biogenic Fossils
sedimentary
Pearl (Cultured Freshwater)
Calcium Carbonate (Aragonite) - CaCO3
mineral
Pearl
Organic Mineraloid (CaCO3 + Conchiolin)
mineral
Pearl
Aragonite and Conchiolin (CaCO3 + organic protein)
mineraloid
Stromatolite
Laminated biogenic sedimentary structure (Cyanobacteria)
sedimentary
Fossiliferous limestone, likely coralline or stromatolitic
Biogenic limestone; predominantly calcite (CaCO₃)
sedimentary
Fossiliferous Chert
Cryptocrystalline quartz (SiO2) with biogenic inclusions
sedimentary
Kidney Stone (Urolith)
Calculus renalis (Biogenic mineral aggregate)
mineral
Stromatolite Fossil
Stromatolite (Cyanobacteria biogenic sedimentary structure)
fossil
Fossiliferous Limestone
Biogenic Sedimentary Rock (primarily CaCO3)
sedimentary
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Coquina
Biogenic Limestone (Calcite/Aragonite, CaCO3)
sedimentary
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Fossiliferous Limestone
Autochthonous Biogenic Sedimentary Rock (CaCO3)
sedimentary