Mother of Pearl (Nacre)
Aragonite with Conchiolin (CaCO3)
Category
Browse biogenic material specimens identified by the Rock Identifier community.
Mother of Pearl (Nacre)
Aragonite with Conchiolin (CaCO3)
Chert (Flint / Chalcedony pebble)
Silicon Dioxide (SiO2)
Fossiliferous Limestone / Fossil Fragment
Calcium Carbonate Matrix with Biogenic Inclusions (CaCO3)
Pearl (Biogenic Mineraloid)
Calcium carbonate (CaCO3) primarily as Aragonite
Freshwater Pearl
Calcium Carbonate (CaCO3) - Aragonite/Calcite organic composite
Chert (Pebble)
Microcrystalline Quartz (SiO2)
Land Snail Shell
Gastropoda (Calcium Carbonate, CaCO3)
Pearl
Calcium carbonate (CaCO3) as Aragonite or Calcite
Pearl
Calcium carbonate (CaCO3) - mainly Aragonite with Conchiolin
Fossilized Tooth Fragment
Vertebrate Fossil (Mammalia indet.)
Rounded flint or chert pebble
Microcrystalline quartz (SiO₂), commonly chalcedony with possible impurities
Fossiliferous Limestone
Biogenic Limestone (CaCO3)
Fossiliferous Limestone
Biogenic Limestone (CaCO3)
Fossiliferous Limestone (Coquina / Shell Limestone)
Biogenic Limestone (CaCO3)
Likely fossilized shell or carbonate concretion
Indeterminate biogenic calcium carbonate, commonly calcite (CaCO₃)
Seashell Fragment (Aragonite/Calcite)
Calcium Carbonate (CaCO3) - Shell fragment
Cleavable Calcite
Calcium Carbonate (CaCO3)
Precious Coral
Corallium rubrum (Calcium Carbonate, CaCO3)
Pearl-embellished decorative cross
Pearl (biogenic calcium carbonate, predominantly aragonite) with rhinestone-mounted glass or synthetic gemstones
Fossiliferous Limestone
Biogenic Sedimentary Rock
Coquina
Biogenic Limestone (Coquina)
Coquina
Biogenic Limestone (CaCO3)
Coquina / Shelly Limestone
Coquina (Biogenic Limestone)
Pearl
Biogenic CaCO3 (Aragonite)
Brachiopod Fossil
Phylum Brachiopoda (likely Order Rhynchonellida or Spiriferida)
Pearl (as a Biogenic Mineral)
Calcium Carbonate (mostly Aragonite) with Conchiolin; CaCO3
Pearl (Pendant)
Calcium Carbonate (Aragonite/Calcite) - CaCO3
Sea Snail Shell (Top Shell)
Trochidae family (Calcium Carbonate, CaCO3)
Banded Chert
Microcrystalline Quartz (SiO2)
Pearl
Calcium Carbonate (CaCO3) - mainly Aragonite and Calcite
Pearl
Organic gemstone (Calcium carbonate / CaCO3 + Conchiolin)
Human Skin (Epidermis/Dermis)
Integumentary tissue (High content of hydroxyapatite in bones, though the surface is biological)
Pearl
Calcium carbonate (CaCO3) - Aragonite/Calcite variety
Fossiliferous Limestone with Brachiopod
Phylum Brachiopoda in calcitic matrix
Hag Stone
Sandstone or Limestone with Solution Holes (Bioturbation/Erosion)
Chert (Arrowhead Point)
Microcrystalline Quartz (SiO2)
Pearl
Calcium Carbonate (Aragonite) - CaCO3
Mother of Pearl (Nacre)
Calcium Carbonate (Aragonite) with organic conchiolin
Pearl (Biogenic)
Nacre / Calcium Carbonate (CaCO3)
Pearl
Calcium carbonate (CaCO3) in the form of Aragonite or Calcite
Fossil Coral
Coral Limestone (a type of biogenic sedimentary rock)
Chert (or Fossiliferous Limestone)
Microcrystalline Quartz (SiO2) / Calcium Carbonate (CaCO3)