Coquina
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Category
Organic Gemstone (Biogenic)
Browse organic gemstone (biogenic) specimens identified by the Rock Identifier community.
Learn about Organic Gemstone (Biogenic) in the encyclopedia
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Pearl
Aragonite (CaCO3) with Conchiolin
mineral
Fossiliferous Limestone
Biogenic Sedimentary Rock (Calcium Carbonate, CaCO3)
sedimentary
Fossiliferous Jasper / Miriam Stone / Elephant Skin Jasper
Biogenic Chalcedony / Silicified Fossiliferous Limestone
fossil
Fossiliferous Limestone
CaCO3 (principally Calcite or Aragonite)
sedimentary
Fossiliferous Limestone
Biogenic Sedimentary Rock (Calcium Carbonate, CaCO3)
sedimentary
Fossiliferous Limestone containing a Brachiopod or Mollusk Impression
Biogenic Sedimentary Rock / Fossiliferous Limestone
sedimentary
Pearl
Calcium Carbonate (CaCO3)
mineral
Flint (chert), likely a worked or fractured nodule
Microcrystalline quartz/chalcedony (SiO₂)
sedimentary
Flint (chert), likely brown flint
Microcrystalline quartz/chalcedony (SiO₂)
sedimentary
Fossiliferous Limestone / Fossil Fragment
Calcium Carbonate (CaCO3) with indeterminate biogenic remains
fossil
Pearl-embellished decorative cross
Pearl (biogenic calcium carbonate, predominantly aragonite) with rhinestone-mounted glass or synthetic gemstones
gemstone
Pearl (as a Biogenic Mineral)
Calcium Carbonate (mostly Aragonite) with Conchiolin; CaCO3
mineral
Tahitian Pearl
Biogenic Calcium Carbonate (Aragonite/Calcite), CaCO3
mineral
Fossiliferous Limestone (Coquina / Shell Limestone)
Bioclastic Limestone (CaCO3)
sedimentary
Pearl
Calcium Carbonate (CaCO3) - mainly Aragonite and Calcite
mineral
Possible fossilized shell or coral fragment
Indeterminate biogenic carbonate, likely calcite (CaCO₃)
fossil
Pearl
Calcium Carbonate (CaCO3) in the form of Aragonite
mineral
Black flint (chert)
Microcrystalline quartz/chalcedony (SiO₂)
sedimentary
Pearl
Calcium Carbonate (CaCO3)
mineral
Pearl (in a decorative hair comb setting)
Calcium carbonate (CaCO3) primarily as Aragonite, bonded with Conchiolin
Organic Mineraloid
Pearl
Aragonite and Calcite (CaCO3) with Conchiolin
mineral
Beaded mineral/crystal jewelry (likely turquoise and coral accents)
Variable; blue beads may be turquoise (CuAl6(PO4)4(OH)8·4H2O), with possible dyed howlite, glass, or composite materials
gemstone
Fossiliferous Limestone (Gastropod / Crinoid Fossil Rock)
Biogenic Sedimentary Rock (CaCO3)
fossil
Amber
Succinite (Organic Gemstone)
mineral
Banded chert or flint
Microcrystalline quartz (SiO₂), likely with iron-oxide and dark organic/mineral impurities
sedimentary
Chert / Flint
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Amber
Succinrite (Organic Gemstone)
mineraloid
Amber
Organic gemstone (Succinite)
mineral
Amber
Succinates (Organic Gemstone)
mineral
Raw Amber / Resin Mineral
Succinite (Fossilized Tree Resin)
gemstone
Pearl
Biogenic Calcium Carbonate (Aragonite and Conchiolin), CaCO3
mineral
Popcorn
Zea mays everta (P. Wilson) (Botanical name for the corn variety)
Organic/Biogenic
Pearl
Calcium Carbonate (Aragonite) - CaCO3
mineral
Amber and Citrine Quartz
Succinite (Amber) and Silicon Dioxide (SiO2 / Citrine)
mineral
Pearl
Aragonite (CaCO3) with Conchiolin
mineral
Pink Pearl
Calcium Carbonate (Aragonite/Calcite) with Conchiolin (CaCO3)
mineral
Pearl
Calcium Carbonate (CaCO3) with Conchiolin
mineral
Amber
Succinicum (C10H16O)
mineral
Amber (Copal)
Fossilized Tree Resin
mineraloid
Chert (often called Flint)
Chert (Microcrystalline Quartz, SiO2)
sedimentary
Tahitian Black Pearl
Biogenic Calcium Carbonate (Aragonite/Conchiolin Mixture), CaCO3
mineral