Red Jasper (Mahogany Obsidian variant similarity)
Silicon Dioxide (SiO2) with iron oxide inclusions
Category
Browse anthropogenic sedimentary (man made) specimens identified by the Rock Identifier community.
Red Jasper (Mahogany Obsidian variant similarity)
Silicon Dioxide (SiO2) with iron oxide inclusions
Fossilized Pycnodonte Oyster
Pycnodonte (Gryphaeostrea) species; Composition is Calcium Carbonate (Calcite/Aragonite)
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)
Yellow Quartzite or Yellow Jasper
Quartzite (primarily SiO2 with Iron oxide staining)
Amber
Succinicum (Formula: C10H16O)
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)
Fossilized Shark Tooth (Otodus obliquus)
Otodus obliquus (composed primarily of Fluorapatite)
Hematite / Goethite (Iron Ore)
Iron Oxide (Fe2O3 / FeO(OH))
Rhodochrosite
Manganese carbonate (MnCO3)
Calamites (Fossilized Horsetail)
Calamites suckowii (Family: Calamitaceae)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Sandstone Beach Pebble
Clastic Sedimentary Rock (primarily Quartz with Iron Oxide coating)
Chert (Grey-Green Var.)
Silicon Dioxide (SiO2)
Fossilized Dinosaur Skull (Tyrannosaurus rex)
Tyrannosaurus rex (permineralized fossil), rich in Hydroxylapatite/Silica
Chert (Septarian or Nodular variety)
Microcrystalline Quartz (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Pyrite on Limestone
Iron Disulfide (FeS2) in Calcium Carbonate (CaCO3) matrix
Quartz (Milky/Bull Quartz)
Silicon Dioxide (SiO2)
Chert (varietal: Jasper or Flint likely, but definitive identification is difficult from image)
SiO₂ (silicon dioxide)
Caliche (with Lichen Cover)
Calcium carbonate-cemented soil layer (CaCO3)
Limonite (Ironstone Concretion)
Limonite (Hydrated iron(III) oxide-hydroxide, mixtures of FeO(OH)·nH2O)
Chalcedony on Matrix
Silicon Dioxide (SiO2)
Hematite
Hematite (Iron(III) oxide, Fe2O3)
Banded Calcite (often sold as Caribbean Calcite or Mexican Onyx)
Calcium Carbonate (CaCO3)
Quartz (Smoky/Grey variety)
Silicon Dioxide (SiO2)
Chert (Jasper/Flint variety)
Silicon Dioxide (SiO2)