Potassium-Rich Silicate Clay (inferred from biological context)
Phyllosilicate group (likely Illite or Smectite within surrounding soil substrate)
mineral
Category
Organic Gemstone
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Travertine
Travertine (a terrestrial form of Limestone, CaCO3)
sedimentary
Fossiliferous Limestone (Shell Fragment)
Biogenic Limestone (Calcium Carbonate / CaCO3)
sedimentary
Fossiliferous Limestone
Carbonate Rock (CaCO3 with organic inclusions)
sedimentary
Flint with Fossil Inclusion
Cryptocrystalline quartz (SiO2) enclosing fossilized organic remains
sedimentary
Petrified Wood
Silicified Wood (SiO2 permineralization)
fossil
Gravel / Limestone Fragment
Calcium Carbonate (CaCO3) / Fine-grained Sedimentary Rock
sedimentary
Amber
Succinate (Fossilized Tree Resin)
mineraloid
Fossilized Tooth Fragment
Vertebrate Fossil (Mammalia indet.)
fossil
Paper (Cellulose)
Cellulose (C6H10O5)n
Organic (Anthropogenic)
Amber
Succinite
mineral
Fossiliferous Kalkstein (Marl/Sandstone)
Fossiliferous calcarenite/siltstone
sedimentary
Limestone and Quartz Gravel with Petrified Wood
Sedimentary gravel aggregate and fossilized wood
sedimentary
Amber
Succinates (Fossilized Resin)
mineral
Shale with Iron Staining
Fissile Mudrock (Sedimentary Rock)
sedimentary
Amber
Amber (Fossilized Tree Resin)
mineral
Likely fossil shell fragment
Indeterminate mollusk fossil; possibly a gastropod or bivalve in limestone
fossil
Moss Agate
SiO2
mineral
Fossiliferous Limestone
Limestone (Calcium Carbonate - CaCO3)
sedimentary
Fossiliferous Limestone
Fossiliferous Limestone (CaCO3)
sedimentary
Mother of Pearl (Nacre) / Shell Fragment
Biogenic Calcium Carbonate (Aragonite and Conchiolin)
fossil
Coarse Sand or Fine Gravel
Detrital Sedimentary Fragments (mostly SiO2)
sedimentary
Limestone Pebble with Crinoid Fossil
Calcium Carbonate (CaCO3) - Fossiliferous Limestone
sedimentary
Fossil Bivalve / Ostreid Shell (Hag Stone / Perforated Pebble)
Phylum Mollusca, Class Bivalvia
fossil
Coal (Bituminous or Anthracite)
Carbonaceous sedimentary rock (primarily Carbon, C)
sedimentary
Limestone with Fossil Inclusion
Sedimentary Calcium Carbonate (CaCO3)
sedimentary
Megalodon Shark Tooth (Partial Fossil)
Otodus megalodon (fossilized in Calcium Phosphate/Apatite)
Mineral/Fossil
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Quartz-veined Limestone
Sedimentary limestone with quartz/calcite veinlets
sedimentary
Chert / Flint
Microcrystalline Quartz (SiO2)
sedimentary
Fossilized Bone Fragment
Vertebrate Fossil
fossil
Manganese-coated Sandstone
Clastic sedimentary rock with Manganese Oxide (often Pyrolusite or Psilomelane)
sedimentary
Fossiliferous Limestone with Rugose Coral
Lithostrotionella (Limestone Matrix - CaCO3)
sedimentary
Knightia Fossil in Limestone
Knightia eocaena in micritic limestone
sedimentary
Amber
Fossilized Resin (C10H16O)
mineral
Amber
Succinite (specifically for Baltic amber); approximate formula C10H16O
Mineraloid
Amber
Succinite (C10H16O)
mineraloid
Manganese Dendrite on Siltstone
Manganese Oxide (pyrolusite or psilomelane) Dendrites
mineral/sedimentary
Amber
Succinate (Fossilized Tree Resin)
fossil
Chert Concretion / Nodule
Microcrystalline Quartz (SiO2)
sedimentary
Amber in Matrix
Succinite (Carbon-based organic polymer)
Organic (Sedimentary context)
Fossiliferous Limestone
Fossiliferous Limestone (CaCO3)
sedimentary