Limestone
Calcium Carbonate (CaCO3)
sedimentary
Category
Mineral (Biogenic)
Browse mineral (biogenic) specimens identified by the Rock Identifier community.
Learn about Mineral (Biogenic) in the encyclopedia
View all →
Chert (Flint / Jasper)
Microcrystalline Quartz (SiO2)
sedimentary
Fossiliferous Limestone (with Crinoids/Coral)
Fossiliferous Limestone (CaCO3)
sedimentary
Limestone with Chert
Calcium Carbonate (CaCO3) with Silica (SiO2) inclusions
sedimentary
White coral limestone (probable fossiliferous limestone)
Calcite (CaCO₃), commonly derived from aragonitic coral skeletons recrystallized to calcite
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
Chert
Cryptocrystalline Quartz (SiO2)
sedimentary
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
Aragonite and Conchiolin (CaCO3 + organic protein)
mineraloid
Chert / Flint
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Fossiliferous Limestone with Crinoid stems
Calcite-rich Biogenic Sedimentary Rock (CaCO3)
sedimentary
Fossiliferous Limestone
Limestone with fossil inclusions (CaCO3)
sedimentary
Fossiliferous Limestone
Limestone (CaCO3) with Crinoid/Bivalve fossils
sedimentary
Chert (Jasper/Limonitic Chert)
Cryptocrystalline Quartz (SiO2) with Iron Oxide (FeO(OH)) inclusions
sedimentary
Chert (Nodule)
Microcrystalline Silica (SiO2)
sedimentary
Fossiliferous Limestone
Calcium Carbonate (CaCO3) with Bioclasts
sedimentary
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Coquina
Bioclastic Limestone
sedimentary
Fossilized Shell in Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Bay Scallop Shell
Argopecten irradians (Biogenic Calcium Carbonate / CaCO3)
sedimentary
Polished brown flint/chert (likely)
Microcrystalline quartz, SiO₂ (chalcedonic flint/chert)
sedimentary
Freshwater Pearl
Calcium Carbonate (CaCO3) in the form of Aragonite and Calcite
gemstone
Chert or flint fragment
Microcrystalline quartz (SiO₂), commonly chalcedony with cryptocrystalline quartz
sedimentary
Chert or flint fragment
Microcrystalline quartz (SiO₂), likely chert/flint
sedimentary
Chert or flint fragment
Microcrystalline quartz (SiO₂), often with chalcedony
sedimentary
Chert (Flint Nodule)
Microcrystalline Quartz (SiO2)
sedimentary
Banded Chert Pebble
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Chert (often called Flint)
Chert (Microcrystalline Quartz, SiO2)
sedimentary
Chert / Flint
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Tahitian Black Pearl
Biogenic Calcium Carbonate (Aragonite/Conchiolin Mixture), CaCO3
mineral
Limestone (Fossiliferous)
Sedimentary Carbonate Rock (CaCO3)
sedimentary
Likely fossilized shell or carbonate concretion
Indeterminate biogenic calcium carbonate, commonly calcite (CaCO₃)
fossil
Flint (Chert Nodules)
SiO2 (Cryptocrystalline Quartz)
sedimentary
Chert (Flint) / Silicified Limestone
Microcrystalline Quartz (SiO2)
sedimentary
Coquina
Biogenic Limestone (Calcium Carbonate - CaCO3)
sedimentary
Stromatolite
Biogenic Sedimentary Rock (composed predominantly of CaCO3)
sedimentary