Pearl
Aragonite and Conchiolin (CaCO3 + organic protein)
mineraloid
Category
Organic (Biological Organism)
Browse organic (biological organism) specimens identified by the Rock Identifier community.
Bituminous Coal
Organic sedimentary rock (humic coal)
sedimentary
Amber
Succinite (Approximate formula: C10H16O)
mineral
Onyx (Black) and Mother of Pearl Inlay
Silicon Dioxide (SiO2) for Onyx; Aragonite (CaCO3) for Mother of Pearl
mineral
Anthracite Coal
Anthracite (Carbon-rich metamorphic coal)
metamorphic
Petrified Wood (Silicified Fossil)
Silicified Wood (SiO2)
sedimentary
Moss Agate
Silicon Dioxide (SiO2) with inclusions of Manganese or Iron oxide
mineral
Cardstock (Paper)
Cellulose (C6H10O5)n
sedimentary (man-made)
Petrified Wood
Silicified Wood (SiO2 permineralization)
sedimentary
Fossil Shell Fragment (possibly Brachiopod or Bivalve)
Calcium Carbonate (CaCO3) - Phylum Brachiopoda or Mollusca
sedimentary
Bituminous Coal (with Anthracite or Vitrinite inclusion)
Organic-rich Sedimentary Rock (Carboniferous classification)
sedimentary
Black Limestone with Calcite Veining
Bituminous Limestone (CaCO3 with Organic Carbon inclusions)
sedimentary
Glauconitic Sandstone (Greensand)
Glauconitic Quartz Arenite (containing Glauconite, (K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2)
sedimentary
Fossiliferous Limestone
Bioclastic Limestone (composition: CaCO3)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
mineral
Fossilized Shell in Limestone
Bivalve fossil (CaCO3) in Carbonate Sedimentary Rock
sedimentary
Amber
Succinite
mineral
Red Coral (with Hematite and Black Pearl accents)
Corallium rubrum (Calcium Carbonate, CaCO3)
mineral
Shell Cameo (Sardonyx Shell)
Cassis madagascariensis (Sardonyx shell)
mineral (biogenic silica/calcium carbonate substrate)
Pearl
Organic gemstone (Calcium carbonate - CaCO3)
mineral
Limestone with Bitumen/Chert
Calcite (CaCO3) containing organic hydrocarbons
sedimentary
Bituminous Coal
Bituminous coal (Organic Sedimentary Rock)
sedimentary
Ambergris
Ambergris (Coprolite-adjacent organic substance)
Organic (Geological interest)
Purple Agate (Dyed Chalcedony)
SiO2 (Silicon Dioxide) with organic dyes
mineral
Bituminous Coal
Organic Sedimentary Rock (Carbon-based)
sedimentary
Dyed Pink Quartzite (Jadeite Simulant)
Silicon Dioxide (SiO2) with organic dye
metamorphic
Coquina or Fossiliferous Limestone
Fossiliferous Calcarenite (CaCO3)
sedimentary
Petrified Wood
Silicified Wood (SiO2 - Silicon Dioxide)
sedimentary
Fossiliferous Limestone (Coquina / Shell Limestone)
Bioclastic Limestone (CaCO3)
sedimentary
Petrified Wood
Silicified Wood (primarily Silicon Dioxide, SiO2)
mineral
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Ironstone Concretion
Siderite or Hematite Concretion
sedimentary
Orthoceras Fossil Limestone
Orthoceras (extinct Cephalopod fossil) in Matrix
sedimentary
Coquina / Shelly Limestone
Coquina (Biogenic Limestone)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Anthracite Coal
Anthracite (Carbon-based metamorphic rock, 86-97% C)
metamorphic
Stromatolite (Fossiliferous Limestone)
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Petrified Wood
Silicified Wood (primarily SiO2 - Silicon Dioxide)
sedimentary
Opalite
Synthetic Opalised Glass
Mineral (Synthetic / Man-made)
Mother of Pearl (Nacre)
Nacre (Aragonite/Conchiolin), CaCO3 + Organic Polymers
mineral
Petrified Wood
Silicon Dioxide (SiO2) permineralized organic matter
sedimentary
Black Pearl (Tahitian or Irradiated Type)
Organic gemstone (Calcium Carbonate with Conchiolin Binding)
mineraloid