Chert (Nodule)
Silicon Dioxide (SiO2)
Category
Browse sedimentary (fossilized) specimens identified by the Rock Identifier community.
Chert (Nodule)
Silicon Dioxide (SiO2)
Red Sandstone
Arenite (predominantly SiO2 with Fe2O3)
Red Sandstone (Iron-rich)
Ferruginous Sandstone (variable formula, primarily SiO2 + Fe2O3)
Pyrite in Shale
Iron Sulfide (FeS2) in Argillaceous Shale
Fancy Jasper
Silicon Dioxide (SiO2) with mineral inclusions
Chert (with Iron Staining)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Sandstone (Grooved/Weathered)
Arenite (composed primarily of Quartz and Lithic fragments)
Chert (Flint variety)
Silicon Dioxide (SiO2)
Red Jasper (Mahogany Obsidian variant similarity)
Silicon Dioxide (SiO2) with iron oxide inclusions
Brown Jasper
Silicon Dioxide (SiO2)
Chert (Flint Pebbles)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Red Chert
Microcrystalline Quartz (SiO2)
Chert (variations include Flint/Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (and Chert-based Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Sandstone
Arenite (primarily SiO2)
Yellow Quartzite or Yellow Jasper
Quartzite (primarily SiO2 with Iron oxide staining)
Quartzite River Rock
Quartzite (primarily SiO2)
Quartz (Druzy)
Silicon Dioxide (SiO2)
Quartz Druze on Matrix
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Limonite (Hydrated Iron Oxide / Bog Iron)
FeO(OH)·nH2O
Quartz Geode (likely within Limestone or Dolomite matrix)
Quartz (SiO₂)
Limonite (Yellow Ochre)
Hydrated iron(III) oxide-hydroxide (FeO(OH)·nH2O)
Petrified Wood
Silicified wood (primarily SiO2 - Silicon Dioxide/Quartz)
Quartzite
Metamorphosed Quartz Sandstone (SiO2)
Carnelian
Carnelian (SiO2 with Iron Oxide impurities)
Banded Slate or Siltstone with Quartz/Calcite Veins
Protolith-derived Siltstone or Slate (varies based on degree of metamorphism)
Quartzite River Stone
Quartzite (primarily SiO2)
Precious Opal
Hydrated amorphous silica (SiO2·nH2O)
Hematite / Goethite (Iron Ore)
Iron Oxide (Fe2O3 / FeO(OH))
Rhodochrosite
Manganese carbonate (MnCO3)
Sandstone Beach Pebble
Clastic Sedimentary Rock (primarily Quartz with Iron Oxide coating)
Sandstone (Ferruginous)
Arenite (with Iron Oxides)
Sandstone
Arenite (SiO2 + various cementing minerals)
Chert (Grey-Green Var.)
Silicon Dioxide (SiO2)
Sandstone (Ferruginous)
Sandstone (Clastic sedimentary rock, predominantly SiO2 with Fe2O3 cement)
Fossiliferous Limestone (Bivalve Fossil)
Calcium Carbonate (CaCO3) with Bivalvia fossil
Sandstone (with Manganese staining)
Arenite (composed primarily of SiO2)
Limestone Pebble
Calcium Carbonate (CaCO3)
Chert (Septarian or Nodular variety)
Microcrystalline Quartz (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Pyrite on Limestone
Iron Disulfide (FeS2) in Calcium Carbonate (CaCO3) matrix