Fossil or modern bivalve shell
Calcium carbonate shell, likely aragonite (CaCO₃); exact species cannot be determined from the image
fossil
Category
Sedimentary (Biogenic Sediment Or Biological Remain)
Browse sedimentary (biogenic sediment or biological remain) specimens identified by the Rock Identifier community.
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Fossiliferous Limestone
Calcium Carbonate (CaCO3) with Biogenic Inclusions
sedimentary
Chalk
Calcium Carbonate (CaCO3) - Biogenic Limestone
sedimentary
Fossiliferous Limestone
Biogenic Limestone (CaCO3 with fossil fragments)
sedimentary
Stromatolite (Fossiliferous Limestone)
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Fossiliferous Limestone
Calcium Carbonate (CaCO3) with Biogenic Inclusions
sedimentary
Coquina
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Fossiliferous Limestone (Murchisonia/Gastropod Limestone)
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Coquina (Fossiliferous Limestone)
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Coquina
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
mineral
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
mineral
Yellow Calcite
Calcium Carbonate (CaCO3)
mineral
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
mineral
Fossiliferous limestone with brachiopod or bryozoan fossils
Calcite (CaCO₃) limestone containing marine invertebrate fossils, possibly brachiopoda or bryozoa
fossil
Chert / Flint
Microcrystalline Quartz (SiO2)
sedimentary
Chert (Nodule)
Silicon Dioxide (SiO2)
sedimentary
Chert (Jasper/Flint variety)
Microcrystalline quartz (SiO2)
sedimentary
Sandstone (with Lichen)
Arenite (composed primarily of SiO2)
sedimentary
Quartz (Grain/Fragment)
Silicon Dioxide (SiO2)
mineral
Sandstone with Lichen and Iron Oxide Staining
Quartz Arenite / Sandstone
sedimentary
Amber
Succinate (Fossilized Tree Resin)
mineraloid
Chert / Flint
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
White Quartz Pebble
Crystalline Silicon Dioxide (SiO2)
mineral
Weathered quartz-rich metamorphic rock, likely quartzite
Quartzite (mostly microcrystalline quartz, SiO₂), possibly altered sandstone
metamorphic
Chert (Yellow Jasper)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Chert (with Quartz/Chalcedony)
Microcrystalline Quartz (SiO2)
sedimentary
Dendritic Limestone
Calcite with Manganese Oxide (Manganese Dendrites)
sedimentary
Yellow calcite
Calcite, CaCO₃
mineral
Chert (Flint)
Microcrystalline Quartz (SiO2)
sedimentary
Optical Calcite
Calcium Carbonate (CaCO3)
mineral
Calcite
Calcium Carbonate (CaCO3)
mineral
Hag Stone
Perforated Sandstone (composed of SiO2 and calcareous cement)
sedimentary
Calcite
Calcium Carbonate (CaCO3)
mineral
Fossil shell fragment (likely bivalve)
Bivalvia indeterminate; shell material chiefly aragonite or calcite (CaCO₃)
fossil
Fossil shark teeth
Probably fossilized shark teeth, possibly *Otodus* or *Carcharhinus* species
fossil
Orange Calcite (likely polished specimen)
Calcite
Mineral
Banded Agate with Drusy Quartz
Cryptocrystalline Quartz (SiO2) with macrocrystalline Quartz
mineral
Chert / Flint
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Fossil-bearing limestone slab
Bioclastic limestone, likely containing brachiopod or bivalve impressions
fossil
Sandstone (Ferruginous)
Arenite with Iron Oxide cement
sedimentary