Chert
Chert (SiO2)
sedimentary
Category
Mineral (Biogenic)
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Fossiliferous Limestone containing a Brachiopod or Mollusk Impression
Biogenic Sedimentary Rock / Fossiliferous Limestone
sedimentary
Fossilized Shell Fragment / Mother of Pearl
Calcium Carbonate (CaCO3) - Aragonite/Calcite biomineral
fossil
Fossiliferous Limestone with Brachiopod
Phylum Brachiopoda in calcitic matrix
sedimentary
Chert (Flint)
Microcrystalline Quartz (SiO2)
sedimentary
Mother of Pearl (Nacre)
Nacre (Aragonite/Conchiolin), CaCO3 + Organic Polymers
mineral
Chert (Arrowhead Point)
Microcrystalline Quartz (SiO2)
sedimentary
Chert Pebble with Quartz Veining
Microcrystalline Quartz (SiO2)
sedimentary
Atlantic Calico Scallop (Biogenic Aragonite/Calcite)
Argopecten gibbus (Chemical: CaCO3)
mineral
Oyster Shell (Aragonite/Calcite)
Calcium Carbonate (CaCO3)
sedimentary
Pearl
Calcium Carbonate (Aragonite) - CaCO3
mineral
Mookaite Jasper
SiO2
Sedimentary
Possible fossilized shell or coral fragment
Indeterminate biogenic carbonate, likely calcite (CaCO₃)
fossil
Chert (or Fossiliferous Limestone)
Microcrystalline Quartz (SiO2) / Calcium Carbonate (CaCO3)
sedimentary
Chalky limestone
Micritic limestone, predominantly calcite (CaCO₃)
sedimentary
Chert (Smoky Variety)
Microcrystalline Quartz (SiO2)
sedimentary
Pearl
Aragonite (CaCO3) with Conchiolin
mineral
Banded Chert / Agate
Silicon Dioxide (SiO2)
sedimentary
Limestone (River Stone)
Calcium Carbonate (CaCO3)
sedimentary
Limestone (Elephant Skin or Karst-weathered)
Calcium Carbonate (CaCO3)
sedimentary
Fossiliferous Chert (Gryphaea Fossil)
Silicon Dioxide (SiO2) with Calcitic Mollusk Remnants
sedimentary
Chert (Pebble)
Silicon Dioxide (SiO2)
sedimentary
Chert (Flint / Agate Nodule)
Silicon Dioxide (SiO2)
sedimentary
Jasper (or Chert)
Microcrystalline Quartz (SiO2)
sedimentary
Fossiliferous Limestone
Calcium Carbonate (CaCO3) with Biogenic Inclusions
sedimentary
Pearl (likely Freshwater or Akoya Cultured)
Aragonite / Conchiolin composite (CaCO3)
Mineralloid (Organic gemstone)
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
Chert (Flint / Jasper / Hornstone)
Microcrystalline Quartz (SiO2)
sedimentary
Chert (varieties include Flint and Jasper)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Coquina
Biogenic Limestone (Calcitic shells)
sedimentary
Coral Fossil / Coral Fragment
Scleractinia / Calcium Carbonate (CaCO3)
fossil
Coquina / Fossiliferous Limestone
Fossiliferous Limestone / CaCO3
sedimentary
Fossiliferous Limestone with Brachiopod
Phylum Brachiopoda in Sedimentary Matrix (CaCO3)
fossil
Fossiliferous Limestone
Limestone (Calcium Carbonate, CaCO3)
sedimentary
Pearl
Biogenic Calcium Carbonate (Aragonite and Conchiolin), CaCO3
mineral
Tahitian Pearl
Biogenic Calcium Carbonate (Aragonite/Calcite), CaCO3
mineral
Black Freshwater Pearls
Biogenic Calcium Carbonate (Aragonite/Calcite), CaCO3
mineral
Fossiliferous Limestone
Biogenic Sedimentary Rock (CaCO3)
sedimentary
Fossiliferous Limestone (Gastropod / Crinoid Fossil Rock)
Biogenic Sedimentary Rock (CaCO3)
fossil
Coal
Biogenic sedimentary rock (Carbon)
sedimentary
Coquina
Biogenic calcarenite / Coquina (CaCO3)
sedimentary
Fossiliferous Limestone Pebble
Biogenic Sedimentary Rock (CaCO3)
fossil