Petrified Wood
Silicified Wood (SiO2)
Category
Browse organic mineral specimens identified by the Rock Identifier community.
Petrified Wood
Silicified Wood (SiO2)
Ironstone Concretion (Ironstone Gourd)
Limonite/Goethite Concretion (FeOO(H))
Petrified Wood
Silicified Wood (SiO2)
Fossiliferous Sandstone / Fossil Fragment
Fossiliferous Sedimentary Matrix with Indeterminate Fossil Material
Chert (and Petrified Wood)
Silicon Dioxide (SiO2)
Chert (varieties include Flint and Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
River Stone (likely Mudstone or Siltstone)
Lutite (Clastic sedimentary rock composed of clay and silt-sized particles)
Chert (Flint Nodules)
Sedimentary cryptocrystalline quartz (SiO2)
Chert (Jasper)
Microcrystalline Quartz (SiO2)
Graphite
Graphite (Chemical Formula: C)
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
Quartz Geode
Silicon Dioxide (SiO2)
Chert (Jasper-like Silicate)
Microcrystalline quartz (SiO2)
Precious Red Coral
Corallium rubrum (Calcium Carbonate, CaCO3)
Chert (Iron-stained)
Silicon Dioxide (SiO2)
Petrified Wood
Fossilized Wood (SiO2 replacing organic matter)
Petrified Wood
Silicon Dioxide (SiO2) permineralized organic matter
Chert (Iron-stained)
Microcrystalline silica (SiO2) with trace Iron oxide (Fe2O3)
Red Chert (Jasper)
Silicon Dioxide (SiO2)
Red Jasper with Fossils
Silicified Fossiliferous Jasper (Chert variant, SiO2)
Petrified Wood
Silicified wood (Quartz replacement of organic wood structure)
Chert (variations include Flint/Jasper)
Cryptocrystalline Quartz (SiO2)
Chert (with Quartz vein)
Chert (Silicon Dioxide, SiO2)
Red Coral
Corallium rubrum (Calcium Carbonate, CaCO3 with Carotenoid pigments)
Fossiliferous Limestone
Calcium Carbonate (CaCO3)
Fossiliferous Rock (likely Dinosaur Fossil in Matrix)
Permineralized Vertebrate Fossil (Calcium Carbonate/Silica replaced bone material)
Petrified Wood
Silicified Wood (SiO2)
Siderite Concretion in Shale
Iron carbonate (FeCO3) in Mudstone/Shale matrix
Chert (variously known as Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (specifically Banded Chert)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Flint)
Chert (Microcrystalline or cryptocrystalline Quartz, SiO2)
Chert (and Limestone)
Chert (consisting of Microcrystalline Quartz, SiO2)
Fossilized Shark Tooth
Elasmobranchii (fossilized matrix/root section)
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified Wood (primarily Chalcedony/Quartz, SiO2)
Petrified Wood
Silicified Wood (primarily Chalcedony/Quartz, SiO2)
Petrified Wood
Silicified Wood (SiO2)
Ammonite Fossil
Ammonoidea (Calcium carbonate - CaCO3)
Chert (Gray Chalcedony)
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified wood (Quartz/Chalcedony replacement) SiO2
Tufa
Calcareous Tufa (Calcium Carbonate, CaCO3)