Mineral Or Sedimentary (If Chert)

Sandstone (lithic wacke)

Arenite / Lithic Wacke (mostly SiO2 with rock fragments)

Sandstone

Arenite (Sedimentary rock composed of sand-sized minerals or rock grains)

Limonite (Iron Ore)

Goethite and related iron hydroxides (FeO(OH)·nH2O)

Sandstone Concretion (Omar or Nut Rock)

Sedimentary Concretion (specifically an 'Omarolluk' or Omar)

Ironstone Concretion (Moqui Marble Type)

Goethite/Hematite-cemented Sandstone Concretion

Kyanite (in Schist Matrix)

Kyanite (Al2SiO5)

River Stone (Quartzite/Siltstone mixture)

Silicon Dioxide (SiO2) based metamorphosed sandstone

Ruby in Kyanite

Corundum in Disthene (Al2SiO5 + Al2O3)

Sandstone (with Limonite staining)

Arenite (primarily SiO2 with FeO(OH)·nH2O)

Sandstone with Quartz Veins

Arenite (primarily SiO2 with Fe2O3 staining)

Pyrite

Iron Disulfide (FeS2)

Turquoise

CuAl6(PO4)4(OH)8·4H2O (Hydrated copper and aluminum phosphate)

Sandstone or Quartzite

Arenite (if sedimentary) / Quartzite (if metamorphic)

Fossil / Permineralized Bone

Tyrannosaurus rex fossil (Hydroxylapatite replaced by various minerals)

Limonite (also known as Yellow Ochre or Brown Hematite)

Limonite (Hydrated iron oxide-hydroxide, FeO(OH)·nH2O)

Amethyst or Smoky Quartz Geode Slice

Crystalline Silicon Dioxide (SiO2) with iron impurities

Pyrite

Iron Sulfide (FeS2)

Jasper

Silicon dioxide (SiO2) with iron oxide inclusions

Quartz (Clear/White)

Silicon Dioxide (SiO2)

Asphalt Concrete

Bituminous Concrete (Anthropic Rock)

Geode (Unopened)

Siliceous Geode (SiO2)

Quartz Geode

Silicon Dioxide (SiO2) within a secondary sedimentary structure

Yellow Jasper

Jasper (Silica-rich Microcrystalline Quartz, SiO2)

Red Jasper

Silicon Dioxide (SiO2) with Iron inclusions

Fancy Jasper (Bloodstone variety)

Silicon Dioxide (SiO2) with iron oxide inclusions

Geode Nodules / Chalcedony Geode

Silicon Dioxide (SiO2) - Amorphous to Cryptocrystalline Quartz

Sandstone Concretion

Sandstone (Sedimentary Rock) with silica or calcite cement

Sandstone (Quartz-rich)

Arenite

Sandstone

Arenite (Clastic Sedimentary Rock)

Sandstone (with Siltstone/Greywacke variations)

Sedimentary Rock (Clastic)

Jasper (likely a variety of Brecciated Jasper or a patterned variety)

Silicon dioxide (SiO2)

Limonite Concretion (Ironstone)

Limonite (FeO(OH)·nH2O) with Goethite and Hematite

Banded Gneiss

Gneiss

Quartz pebble

Silicon dioxide (SiO2)

Milky Quartz (Vein Quartz)

Silicon Dioxide (SiO2)

Iron-stained Quartz (with Limonite/Hematite)

Silicon Dioxide (SiO2) with Iron Oxide inclusions (FeO(OH) or Fe2O3)

Pyrite in Matrix (Fool's Gold)

Iron Sulfide (FeS2)

Sandstone

Arenite

Sandstone (Ferruginous)

Arenite (primarily SiO2 with Fe2O3 staining)

Dalmatian Stone

Peralkaline rhyolite

Dalmatian Jasper

Dalmatian Stone (comprised of Feldspar, Quartz, and Arfvedsonite)

Sandstone (Ferruginous)

Arenite (primarily SiO2 with Fe2O3 inclusions)