Siltstone
Siltstone (primarily SiO2 with Al2O3)
Category
Browse sedimentary specimens identified by the Rock Identifier community.
Siltstone
Siltstone (primarily SiO2 with Al2O3)
Red Sandstone
Quartz Arenite (with Iron Oxide)
Limonite Concretion (Ironstone)
Limonite (FeO(OH)·nH2O) with Goethite and Hematite
Chert (often called Flint or Jasper)
Chert (Microcrystalline or Cryptocrystalline Silica, SiO2)
Banded Chert (Flint)
Cryptocrystalline Quartz (SiO2)
Banded Siltstone
Siltstone (primarily SiO2 with Al2O3)
Fossilized Bone Fragment
Permineralized Vertebrate Bone (Hydrox yapatite replaced by Silica or Calcite)
Septarian Nodule
Septarian Concretion (Complex of Calcite, Aragonite, and Limestone/Mudstone)
Ferruginous Sandstone (Gozzan-like)
Ferruginous Sandstone (SiO2 with FeO(OH) inclusions)
Chert (specifically Black Chert / Flint)
Silicon Dioxide (SiO2)
Chert (also known as Flint or Common Chalcedony)
Cryptocrystalline Silica (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Red Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
Bored Siltstone (Holey Rock)
Siltstone with Pholad borings (Lithophaga/Pholadidae trace fossils)
Jasper or Chert with Quartz Vugs
Silicon Dioxide (SiO2)
Red Sandstone
Arenite (primarily composed of SiO2 with Fe2O3 cement)
Chert (Flint/Jasper variety)
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified wood (Quartz, Chalcedony, or Opal)
Red Sandstone
Arenite (primarily SiO2 with Fe2O3)
Red Jasper (Chert)
Silicon Dioxide (SiO2) with Iron Oxide inclusions
Orthoceratid Fossil in Limestone
Orthoceras (extinct genus of Nautiloid Cephalopod)
Petrified Wood
Silicified Wood (primarily Quartz / Chalcedony: SiO2)
Chert
Chert (SiO2)
Sandstone (Ferruginous)
Arenite with Iron Oxide cement
Sandstone (with garnet granules)
Clastic sedimentary rock (primarily SiO2 with Fe3Al2(SiO4)3 inclusions)
Ferruginous Sandstone (Ironstone)
Clastic Sedimentary Rock (composed of SiO2 with Fe2O3/FeO(OH) cement)
Ferruginous Sandstone (Ironstone)
Sedimentary rock with high iron oxide content (Fe2O3 / FeO(OH))
Red Sandstone
Clastic sedimentary rock (primarily SiO2 with Fe2O3 iron oxide staining)
Sandstone
Arenite (primarily SiO2)
Geode with Quartz and Chalcedony
Silicon Dioxide (SiO2)
Ferruginous Sandstone
Arenite with Iron Oxide cement (Fe2O3 / FeO(OH))
Limestone
Calcium Carbonate (CaCO3)
Sandstone (Ferruginous)
Arenite with Iron Oxide cement (SiO2 + Fe2O3)
Sandstone
Arenite
Limestone
Calcium Carbonate (CaCO3)
Limonitic Sandstone with Inclusion
Limonitic Quartz Sandstone (primarily SiO2 with FeO(OH)·nH2O)
Sandstone (Yellow/Tan)
Clastic sedimentary rock (primarily SiO2 with iron oxide staining)
Chert
Chert (Microcrystalline Silica, SiO2)
Sandstone
Arenite (primarily SiO2)
Limestone
Calcium Carbonate (CaCO3)
Shale or Siltstone
Sedimentary Clastic Rock (Variable mineral composition including quartz and clay minerals)
Limestone
Calcium Carbonate (primarily CaCO3 as Calcite or Aragonite)