Fossiliferous Limestone
Calcite (CaCO3) matrix with biogenic fragments
Category
Browse biogenic material specimens identified by the Rock Identifier community.
Fossiliferous Limestone
Calcite (CaCO3) matrix with biogenic fragments
Fossiliferous Limestone (Coquina / Shell Limestone)
Biogenic Limestone (Calcium Carbonate, CaCO3)
Chert (Pink/Red variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert / Flint (or lithic artifact flake)
Microcrystalline Quartz (SiO2)
Chert or flint with chalcedony/quartz veins
Microcrystalline silica: primarily quartz (SiO₂), including chalcedony; possible fossiliferous limestone or silicified material
Fossiliferous Limestone
Biogenic Sedimentary Rock (Calcite, CaCO3)
Chert (Agate / Jasper pebble)
Microcrystalline Quartz (SiO2)
Likely weathered gray flint/chert pebble
Microcrystalline quartz (SiO₂), commonly with chalcedony and minor impurities
Coquina
Biogenic Limestone (Calcium Carbonate, CaCO3)
Coquina or Fossilized Shell Fragment
Calcium Carbonate (CaCO3) / Biogenic Limestone
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
Chert Fossil (Pebble)
Microcrystalline Quartz (SiO2) with biogenic inclusions
Chert (Nodule)
Microcrystalline Silica (SiO2)
Chert (Flint Nodule)
Microcrystalline Quartz (SiO2)
Coquina or Fossiliferous Limestone
Biogenic Limestone (Calcite/Aragonite CaCO3)
Chert (and associated Flint)
Silicon Dioxide (SiO2)
Nacre (Mother of Pearl)
Nacre (Biogenic Aragonite/Calcite composite, CaCO3)
Kidney Stone
Nephrolithiasis (Calcium Oxalate, Hydroxyapatite, or Uric Acid)
Fossiliferous Jasper / Miriam Stone / Elephant Skin Jasper
Biogenic Chalcedony / Silicified Fossiliferous Limestone
Fossiliferous Limestone (Coquina-like)
Biogenic Limestone
Coquina
Biogenic Limestone (Calcium Carbonate, CaCO3)
Chert / Flint (with Jasper inclusions)
Microcrystalline Quartz (SiO2)
Chert / Flint
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
Coquina
Biogenic Limestone (Calcium Carbonate, CaCO3)
Fossiliferous Limestone (Coquina / Shell Limestone)
Biogenic Limestone (Calcium Carbonate, CaCO3)
Fossilized Shell Fragment / Mother of Pearl
Calcium Carbonate (CaCO3) - Aragonite/Calcite biomineral
Coquina
Biogenic Limestone (Calcium Carbonate, CaCO3)
Coquina
Biogenic Limestone (Calcite/Aragonite base, CaCO3)
Pearl
Aragonite (CaCO3) with Conchiolin
Coquina
Biogenic Limestone (Calcium Carbonate, CaCO3)
Flint (chert), likely brown flint
Microcrystalline quartz/chalcedony (SiO₂)
Fossiliferous Limestone / Fossil Fragment
Calcium Carbonate (CaCO3) with indeterminate biogenic remains
Chert
Microcrystalline Quartz (SiO2)
Chert with Fossil inclusions
Microcrystalline Quartz (SiO2) with biogenic inclusions
Chert (Nodular Chert)
Microcrystalline or Cryptocrystalline Silicon Dioxide (SiO2)
Coquina
Biogenic Limestone (Calcium Carbonate - CaCO3)
Chalk / Sedimentary Limestone
Calcium Carbonate (CaCO3) - Biogenic Sedimentary Rock
Chert
Chert (Microcrystalline Quartz, SiO2)
Flint (Chert Nodules)
SiO2 (Cryptocrystalline Quartz)
Fossiliferous Limestone
Biogenic Sedimentary Rock (Calcium Carbonate, CaCO3)
Seashell (Calcium Carbonate)
Calcium Carbonate (CaCO3)