Pearl
Calcium Carbonate (CaCO3) in the form of Aragonite
mineral
Category
Mineral Like Biological Tissue
Browse mineral like biological tissue specimens identified by the Rock Identifier community.
Learn about Mineral Like Biological Tissue in the encyclopedia
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Obsidian
Volcanic Glass (SiO2)
igneous
Brachiopod Fossil
Phylum Brachiopoda (likely Order Rhynchonellida or Spiriferida)
fossil
Kidney Stone (Urolith)
Calculus renalis (Biogenic mineral aggregate)
mineral
Petrified Wood
Silicified wood (Quartz/Chalcedony replacement)
fossil
Pyrite
Iron Sulfide (FeS2)
mineral
Fossil Coral (Petoskey Stone / Hexagonaria)
Hexagonaria percarinata (Silicified/Calcite Replacement Coral)
fossil
Chert
Chert (SiO2)
sedimentary
Fossilized Shark Tooth
Chondrichthyes (Class)
fossil
Lepidodendron Fossil (Scale Tree)
Lepidodendron sp.
fossil
Piddock bored rock (likely Mudstone or Shale)
Ichnofossil (Gastrochaenolites borings) in Fine-grained Sedimentary Rock
sedimentary
Biological Bone (Patella/Knee)
Patella (part of the Human Skeletal System)
Organic Structure (Not a Rock)
Pearl
Calcium Carbonate (primarily Aragonite and Calcite), CaCO3
mineral
Coral Fossil (Scleractinia)
Scleractinia (Order), primarily CaCO3 (Aragonite or Calcite)
sedimentary
Pearl
Calcium Carbonate (CaCO3) in the form of orthorhombic Aragonite and Conchiolin
mineral
Precious Red Coral
Corallium rubrum (Calcium Carbonate, CaCO3)
Mineral (Organic Gemstone)
Calcite
Calcium Carbonate (CaCO3)
mineral
Amber
Succinite (fossilized resin)
mineral
Chert Nodule (Fossiliferous Chert)
Microcrystalline Quartz (SiO2)
sedimentary
Red Moss Agate (Jasper)
Silicon Dioxide (SiO2) with Iron Oxide inclusions
sedimentary
Pearl
Biogenic CaCO3 (Aragonite and Calcite)
mineral
Pearl
Calcium Carbonate (Aragonite/Calcite mixed with Conchiolin), CaCO3
mineral
Calcite
Calcium Carbonate (CaCO3)
mineral
Megalodon Shark Tooth Fossil
Otodus megalodon (fossilized in sedimentary matrix)
sedimentary
Amber
Succinite (fossilized tree resin)
fossil
Fossilized Brachiopod
Phylum Brachiopoda (replaced by Calcite/CaCO3)
sedimentary
Pyrite
Iron Disulfide (FeS2)
mineral
Petrified Wood
Silicified Wood (SiO2 permineralization)
sedimentary
Limonitic Sandstone with Inclusion
Limonitic Quartz Sandstone (primarily SiO2 with FeO(OH)·nH2O)
sedimentary
Aragonite (Star Cluster or Twinned variety)
Aragonite (Calcium Carbonate, CaCO3)
mineral
Septarian Nodule
Septarian Concretion (Composition: Calcite, Aragonite, and Limestone/Clay)
sedimentary
Chert
Chert (Microcrystalline Quartz, SiO2)
sedimentary
Sandstone (with biological crust)
Arenite (SiO2 based)
sedimentary
Amber
Succinite
mineraloid
Amber
Succinite (C10H16O)
mineraloid
Chert (Flint)
Microcrystalline Quartz (SiO2)
sedimentary
Calcite
Calcium Carbonate (CaCO3)
mineral
Ironstone Concretion (Limonite/Goethite)
Goethite/Limonite concretion (FeO(OH)·nH2O)
sedimentary
Brachiopod Fossil in Limestone
Phylum Brachiopoda embedded in sedimentary rock
fossil
Fossil crinoid stem segment (columnal)
Crinoidea; commonly preserved as calcite ossicles, often called entrocrinite
fossil
Chert (Nodule)
Silicon Dioxide (SiO2)
sedimentary
Fossilized Fish Skeleton in Matrix
Vertebrata (Class: Actinopterygii), typically found in limestone or shale matrices
sedimentary