Petrified Wood
Silicified Wood (SiO2 as Quartz/Chert/Chalcedony)
Category
Browse sedimentary (biogenic) specimens identified by the Rock Identifier community.
Petrified Wood
Silicified Wood (SiO2 as Quartz/Chert/Chalcedony)
Ferruginous Sandstone
Sandstone (arenite) with Limonite/Goethite cement
Sandstone
Arenite (composed primarily of SiO2)
Chert (Pink variety/Jasper)
Silicon Dioxide (SiO2)
Chert / Flint Pebble
Silicon Dioxide (SiO2)
Chert (Fossiliferous)
Chert (Cryptocrystalline Silica/SiO2)
Chert (specifically Yellow Jasper variety)
Silicon Dioxide (SiO2)
Chert (Jasper)
Silicon dioxide (SiO2)
Chert / Flint
Chert (Microcrystalline Quartz, SiO2)
Chert (often called Flint or Jasper when pigmented)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Chert (Green variety)
Microcrystalline Quartz (SiO2)
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
Chert (Chert Nodule in Limestone Host)
Chert (SiO2)
Chert (Black Chert / Flint)
Silicon Dioxide (SiO2)
Red Sandstone
Arenic rock (composed mainly of SiO2 with Fe2O3)
Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, formula: SiO2)
Sandstone (with garnet granules)
Clastic sedimentary rock (primarily SiO2 with Fe3Al2(SiO4)3 inclusions)
Ferruginous Sandstone (Ironstone)
Sedimentary rock with high iron oxide content (Fe2O3 / FeO(OH))
Ferruginous Sandstone (Ironstone)
Clastic Sedimentary Rock (composed of SiO2 with Fe2O3/FeO(OH) cement)
Red Sandstone
Clastic sedimentary rock (primarily SiO2 with Fe2O3 iron oxide staining)
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Chert
Chert (SiO2)
Sandstone (Ferruginous)
Arenite with Iron Oxide cement
Quartz Geode
Silicon Dioxide (SiO2) within a sedimentary or volcanic shell
Geode with Quartz and Chalcedony
Silicon Dioxide (SiO2)
Ferruginous Sandstone
Arenite with Iron Oxide cement (Fe2O3 / FeO(OH))
Sandstone
Arenite (primarily SiO2)
Limestone
Calcium Carbonate (CaCO3)
Sandstone
Arenite
Sandstone (Ferruginous)
Arenite with Iron Oxide cement (SiO2 + Fe2O3)
Limestone
Calcium Carbonate (CaCO3)
Limonitic Sandstone with Inclusion
Limonitic Quartz Sandstone (primarily SiO2 with FeO(OH)·nH2O)
Shale or Siltstone
Sedimentary Clastic Rock (Variable mineral composition including quartz and clay minerals)
Sandstone (Yellow/Tan)
Clastic sedimentary rock (primarily SiO2 with iron oxide staining)
Chert
Chert (Microcrystalline Silica, SiO2)
Limestone
Calcium Carbonate (primarily CaCO3 as Calcite or Aragonite)
Limestone with Calcite Crystals
Calcium Carbonate (CaCO3)
Fossiliferous Chert (with Brachiopod or Mollusk fragments)
Silicon dioxide (SiO2) with Calcium Carbonate (CaCO3) inclusions
Sandstone (likely Fossilized Wood or Concrete Simulacrum)
Arenite / Silicified Wood / Anthropogenic Concrete
Chert (Brecciated Chert)
Silicon Dioxide (SiO2)
Limestone
Calcium Carbonate (CaCO3)
Sandstone
Arenite (primarily SiO2)