Chert (Flint variety)
Silicon Dioxide (SiO2)
Category
Browse sedimentary specimens identified by the Rock Identifier community.
Chert (Flint variety)
Silicon Dioxide (SiO2)
Fossilized Pycnodonte Oyster
Pycnodonte (Gryphaeostrea) species; Composition is Calcium Carbonate (Calcite/Aragonite)
Chert (and Chert-based Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Sandstone
Arenite (primarily SiO2)
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)
Shale
Fissile Clay-dominant Mudrock (SiO2, Al2O3, K2O, Na2O, CaO, MgO)
Banded Sandstone
Arenite (composed primarily of Quartz: SiO2)
Jasper
Silicon dioxide (SiO2)
Red Sandstone
Arenite (with Iron Oxide cement)
Chert (Arrowhead/Artifact Fragment)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert (often called Flint or Jasper depending on color)
Chert (SiO2 - Microcrystalline or Cryptocrystalline Quartz)
Ironstone Concretion / Limonite Node
Ferruginous Sedimentary Rock (composed primarily of Limonite FeO(OH)·nH2O and Goethite)
Sandstone Beach Pebble
Clastic Sedimentary Rock (primarily Quartz with Iron Oxide coating)
Sandstone (Ferruginous)
Arenite (with Iron Oxides)
Chert (Grey-Green Var.)
Silicon Dioxide (SiO2)
Sandstone
Arenite (SiO2 + various cementing minerals)
Sandstone (with Manganese staining)
Arenite (composed primarily of SiO2)
Fossiliferous Limestone (Bivalve Fossil)
Calcium Carbonate (CaCO3) with Bivalvia fossil
Limestone Pebble
Calcium Carbonate (CaCO3)
Sandstone (Ferruginous)
Sandstone (Clastic sedimentary rock, predominantly SiO2 with Fe2O3 cement)
Fossilized Dinosaur Skull (Tyrannosaurus rex)
Tyrannosaurus rex (permineralized fossil), rich in Hydroxylapatite/Silica
Chert (Septarian or Nodular variety)
Microcrystalline Quartz (SiO2)
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)
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
Metamorphosed Quartz Sandstone (SiO2)
Fossilized Shark Tooth (Otodus obliquus)
Otodus obliquus (composed primarily of Fluorapatite)
Quartzite River Stone
Quartzite (primarily SiO2)
Precious Opal
Hydrated amorphous silica (SiO2·nH2O)
Rhodochrosite
Manganese carbonate (MnCO3)
Hematite / Goethite (Iron Ore)
Iron Oxide (Fe2O3 / FeO(OH))
Chert (Flint)
Microcrystalline Quartz (SiO2)
Pyrite on Limestone
Iron Disulfide (FeS2) in Calcium Carbonate (CaCO3) matrix
Quartzite River Rock
Quartzite (primarily SiO2)
Amber
Succinicum (Formula: C10H16O)
Yellow Quartzite or Yellow Jasper
Quartzite (primarily SiO2 with Iron oxide staining)