Coral Fossil (Scleractinia)
Scleractinia (Order), primarily CaCO3 (Aragonite or Calcite)
sedimentary
Category
Sedimentary (Biogenic Sediment Or Biological Remain)
Browse sedimentary (biogenic sediment or biological remain) specimens identified by the Rock Identifier community.
Fossiliferous Limestone (Crinoidal)
Bioclastic Limestone (predominantly CaCO3)
sedimentary
Chert (specifically Flint or Gray Chert)
Silicon Dioxide (SiO2)
sedimentary
Pyrite
Iron Sulfide (FeS2)
mineral
Sandstone (with biological crust)
Arenite (SiO2 based)
sedimentary
Chert (variant Flint/Novaculite)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Weathered Quartzite or Chert Pebble
Silicon Dioxide (SiO2)
metamorphic or sedimentary
Calcite
Calcium Carbonate (CaCO3)
mineral
Pyrite
Iron Disulfide (FeS2)
mineral
Sandstone (Weathered Cobble)
Clastic sedimentary rock (primarily SiO2)
sedimentary
Chert (Flint)
Microcrystalline or cryptocrystalline quartz (SiO2)
sedimentary
Petrified Wood
Silicified wood (primarily Silicon Dioxide - SiO2)
mineral (silicate-replaced organic material)
Pebble (likely Quartz or Chert)
SiO₂ (Silicon Dioxide) - referring to the likely main mineral composition, Quartz. If it's chert, the scientific name remains SiO₂ with a microcrystalline structure.
Sedimentary Rock
Shale
Lutaceous sedimentary rock
sedimentary
Sandstone Concretion
Ferruginous Sandstone Concretion (Primarily SiO2 with Iron Oxide cement)
sedimentary
Limonite (Hydrated Iron Oxide / Bog Iron)
FeO(OH)·nH2O
Mineral (Sedimentary context)
Megalodon Shark Tooth Fossil
Otodus megalodon
sedimentary
Aragonite Star Cluster
Aragonite (Calcium Carbonate, CaCO3)
mineral
Pyrite (Iron Pyrites)
Iron Sulfide (FeS2)
mineral
Fossiliferous Limestone
Limestone with fossil inclusions (CaCO3)
sedimentary
Piddock-bored Mudstone
Lutite (Siltstone or Mudstone) with Pholad borings
sedimentary
Fossiliferous Limestone (Crinoidal)
Crinoid Limestone (CaCO3 with fossil biological remains)
sedimentary
Dendritic Agate or Manganese Nodule in Chert/Limestone
Silicon Dioxide (SiO2) with Manganese Oxide (MnO2) inclusions
sedimentary
Petrified Wood (Jet or Coalified Wood appearance)
Silicified wood (principally SiO2) or Carbonized Wood
sedimentary
Flint
Chert (a form of cryptocrystalline quartz, chemical formula SiO₂)
Mineral
Blue Calcite
Calcite (Calcium Carbonate, CaCO3)
mineral
Chert (Flint)
Microcrystalline Quartz (SiO2)
sedimentary
Coquina or Fossiliferous Limestone
Biogenic Limestone (Calcite/Aragonite CaCO3)
sedimentary
Fossiliferous Limestone (Coquina / Shell Limestone)
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Coquina
Biogenic Limestone (Calcium Carbonate - CaCO3)
sedimentary
Coquina
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Fossiliferous Limestone (Coquina)
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Coquina / Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate - CaCO3)
sedimentary
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Fossiliferous Limestone (Crinoidal Limestone)
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Coquina
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Coquina
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Fossiliferous Limestone (Coquina)
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Chalk (Sedimentary Pebble)
Calcium Carbonate (CaCO3) - Biogenic Limestone
sedimentary
Fossiliferous Limestone (Coquina / Shell Limestone)
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Coquina Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Fossiliferous Limestone (Coquina / Shell Bed)
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary