Petrified Wood
Silicified wood (Quartz/Chalcedony - SiO2)
sedimentary
Category
Organic Materia (Not A Rock Or Mineral)
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Petrified wood
Silicified wood, commonly quartz (SiO₂) replacing woody tissue
fossil
Shale (or Slate / Coal / Jet)
Laminated fine-grained sedimentary rock (predominantly clay minerals)
sedimentary
Petrified Wood
Silicified Wood (primarily SiO2)
sedimentary
Geode with Quartz Crystal Cavity
Silicon Dioxide (SiO2) in Calcareous/Siliceous Matrix
sedimentary
Chert (Green Fossilized Algae or Jasper)
Silicon Dioxide (SiO2)
sedimentary
Fossilized coral (likely honeycomb or branching coral)
Fossil coral; probable Scleractinia or Tabulata, composition mainly microcrystalline CaCO₃
fossil
Fossiliferous Shale
Laminated Mudrock with plant fossils
sedimentary
Sandstone (likely Arkose or Quartz Sandstone)
Arenite (SiO2 principal component)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
mineral
Tree Agate
Silicon Dioxide (SiO2) with Dendritic Inclusions
Mineral
Limestone
Calcareous sedimentary rock (CaCO3)
sedimentary
Chert (Flint Nodules)
Chert (Silicon Dioxide, SiO2)
sedimentary
Amber (Rough Baltics/Beach Specimen)
Succinicum (Organic Gemstone - Fossilized Resin)
mineral
Septarian Nodule
Septarian Nodule (Calcite, Aragonite, and Limestone/Claystone)
sedimentary
Fossilized Shark Tooth
Chondrichthyes (Class)
fossil
Chert (Yellow Jasper)
Microcrystalline Quartz (SiO2)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
fossil
Polished agate (likely plume or moss agate)
Chalcedony, microcrystalline quartz (SiO₂), with iron-oxide and possible chlorite inclusions
mineral
Ironstone Concretion
Ironstone (Siderite/Goethite/Hematite matrix)
sedimentary
Limestone and Quartz Gravel with Petrified Wood
Sedimentary gravel aggregate and fossilized wood
sedimentary
Fossilized Shark Tooth
Chondrichthyes (class) fossilized tooth
fossil
Fossilized Bivalve Shell
Bivalvia (Phylum Mollusca)
fossil
Dinosaur Fossil Tooth
Vertebrate Fossilized Tooth
fossil
Granite / Feldspar gravel
Granite (felsic intrusive igneous rock)
igneous
Shale with Coprolite influence
Argillaceous sedimentary rock (Shale/Mudstone)
sedimentary
Agatized Petrified Wood
Silicon Dioxide (SiO2) - Chalcedony pseudomorph after Wood
metamorphic
Shale (possibly Carbonaceous or Oil Shale)
Argillaceous Sedimentary Rock
sedimentary
Moss Agate
Silicon Dioxide (SiO2) with inclusions
mineral
Chert (Flint)
Silicon Dioxide (SiO2)
sedimentary
Sandstone
Arenicola (comprising mostly Quartz, SiO2)
sedimentary
Sandstone (Glauconitic)
Glauconitic Quartz Sandstone (SiO2 + (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2)
sedimentary
Shungite
Shungite (carbon-rich Precambrian rock)
mineral
Moss Agate
Silicon Dioxide (SiO2) with inclusions
mineral
Bivalve Fossil (Fossilized Shell)
Class Bivalvia (fossilized in Calcium Carbonate/Aragonite)
fossil
Glauconite (Greensand)
(K, Na)(Fe3⁰, Al, Mg)₂(Si, Al)₄O₁₀(OH)₂
sedimentary
Concretion (likely iron-rich sandstone or claystone concretion)
Diagenetic carbonate/iron-oxide concretion; exact mineralogy requires testing
sedimentary
Fossilized Shark Tooth
Chondrichthyes (Class) fossilized tooth
fossil
Tree Agate
Dendritic Agate (Silicon Dioxide, SiO2 with chlorite inclusions)
mineral
Shale
Clastic sedimentary rock (primarily clay and silt minerals)
sedimentary
Fossil Shark Tooth
Chondrichthyes tooth fossil
fossil
Travertine (Tufa)
Chemical Sedimentary Rock / Travertine (CaCO3)
sedimentary