Petrified Wood
Silicified Wood (primarily SiO2)
fossil
Category
Organic (Anthropogenic)
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Limestone with Lichen
Calcium Carbonate (CaCO3) with Endolithic/Epilithic Lichen
sedimentary
Fossiliferous Limestone
Bioclastic Limestone (CaCO3)
sedimentary
Fossiliferous Limestone
Fossiliferous Limestone (Sedimentary Rock)
fossil
Orthoceras Fossil Limestone
Orthoceras (extinct Cephalopod fossil) in Matrix
sedimentary
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Fossilized Rugose Coral (Horn Coral)
Order Rugosa
sedimentary
Coquina / Shelly Limestone
Coquina (Biogenic Limestone)
sedimentary
Petrified Wood
Silicified Wood (SiO2 permineralization)
fossil
Black Dolomite
Bituminous Dolomite (CaMg(CO3)2)
sedimentary
Bituminous Coal
Organic Sedimentary Rock (Carbon-based)
sedimentary
Amber
Fossilized Tree Resin (Organic Polymer)
gemstone
Mother of Pearl (Nacre)
Calcium Carbonate (Aragonite) with organic conchiolin
gemstone
Coal (Bituminous / Anthracite)
Organic Sedimentary Rock (Carbonaceous Rock)
sedimentary
Coal
Coal (Sedimentary Rock / Organic Rock)
sedimentary
Fossiliferous Limestone
Fossiliferous Limestone (CaCO3 with organic inclusions)
fossil
Ambergris
Ambergris (Coprolite-adjacent/Organic secretion)
mineraloid
Pearl
Aragonite and Conchiolin (CaCO3 + organic protein)
mineraloid
Amber
Succinicum (Organic polymer, largely C10H16O)
Organic Mineral
Bituminous Coal
Organic sedimentary rock (humic coal)
sedimentary
Glauconitic Sandstone (Greensand)
Glauconitic Quartz Arenite (containing Glauconite, (K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2)
sedimentary
Shale
Laminated Fissile Pelite
sedimentary
Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, SiO2)
fossil
Fossilized Shark Tooth
Chondrichthyes (class)
fossil
Chert (varieties include Flint and Jasper)
Microcrystalline or Cryptocrystalline Silicon Dioxide (SiO2)
sedimentary
Chert (specifically Gray/Black Chert)
Chert (Microcrystalline or Cryptocrystalline Quartz, SiO2)
sedimentary
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Chert (specifically Flint or Dark Chert)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Small seashell fossil or shell fragment
Likely calcium-carbonate shell material, chiefly aragonite or calcite; exact species indeterminate
fossil
Pearl
Calcium Carbonate (Aragonite) with Conchiolin; formula: CaCO3
mineral
Limestone
Sedimentary Rock (Primarily CaCO3)
sedimentary
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Chert Nodule / Ironstone Concretion
Microcrystalline Quartz (SiO2) with Iron Oxides
sedimentary
Polished amber-colored stone, possibly chert or jasper
Uncertain from image; likely microcrystalline quartz (SiO₂) if chert/jasper
mineral
Weathered limestone or calcareous fossil fragment
Calcite-rich carbonate rock (CaCO₃), possibly fossiliferous limestone
sedimentary
Siltstone with plant fossil impression
Sedimentary rock with Archaeopteris or Calamites flora impression
fossil
Amber
Succinite (Fossilized Tree Resin)
gemstone
Granite / Feldspar gravel
Granite (felsic intrusive igneous rock)
igneous
Moss Agate
Chalcedony (SiO2) with inclusions of hornblende or chlorite
mineral
Amber
Succinite (C10H16O)
gemstone
Amber
Succinite (C10H16O)
gemstone