Sedimentary (Silicified Fossiliferous Chalcedony)

Sandstone (River Cobble)

Clastic Sedimentary Rock (primarily Quartz with Feldspar)

Quartz Veined Siltstone or Graywacke

Clastic Sedimentary Rock with Quartz (SiO2) veining

Sandstone (Red Flagstone)

Clastic sedimentary rock (primarily Quartz - SiO2)

Sandstone (Ferruginous)

Clastic Sedimentary Rock (SiO2 with FeO/Fe2O3)

Sandstone Chert/Quartzite

Silicon Dioxide (SiO2) - Sedimentary Sandstone / Orthoquartzite

Yellow Calcite

Calcium Carbonate (CaCO3)

Quartz Geode

Silicon Dioxide (SiO2) within a geode

Kyanite

Kyanite (Al2SiO5)

Quartz Geode

Silicon Dioxide (SiO2)

Pyrite

Iron Sulfide (FeS2)

Limonite

Limonite (Hydrous iron oxides, predominantly Goethite FeO(OH)·nH2O)

Pyrite and Sunstone

Iron Sulfide (FeS2) and Plagioclase Feldspar ((Ca,Na)Al(Al,Si)Si2O8)

Carnelian

Carnelian (SiO2)

Satin Spar (Selenite)

Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O

Chert (Tripolitic Chert / Flint Nodules)

Microcrystalline Quartz (SiO2)

Sandstone (Quartz Sandstone)

Clastic sedimentary rock (primarily SiO2)

Limestone

Calcite-rich Sedimentary Rock (CaCO3)

Sandstone (Beach Pebble)

Clastic sedimentary rock (primarily Quartz and Feldspar)

Sandstone (with potential mineral inclusions)

Clastic sedimentary rock (primarily Quartz, SiO2)

Sandstone (Ferruginous/Red Sandstone)

Clastic sedimentary rock (primarily SiO2 with Fe2O3)

Sandstone (likely Arkosic or Lithic)

Clastic Sedimentary Rock (SiO2 with accessory minerals)

Sandstone

Clastic Sedimentary Rock (composed primarily of Quartz: SiO2)

Sandstone Concretion

Clastic Sedimentary Concretion (primarily SiO2 with Fe2O3 cement)

Sandstone

Arenite (often composed of Quartz, SiO2)

Sandstone

Arenite (primarily SiO2 with various cementing agents)

Sandstone (Weathered Pebble)

Arenite (primarily SiO2)

Sandstone (Ferruginous/Banded)

Clastic Terrigenous Sandstone (SiO2 with Fe2O3 cement)

Sandstone (Greywacke/Lithic Sandstone)

Arenite / Lithic Sandstone

Limestone with Calcite Veining

Calcium Carbonate (CaCO3)

Limestone (specifically Travertine or Tufa)

Calcium Carbonate (CaCO3)

Sandstone

Arenite (composed primarily of SiO2)

Ferruginous Sandstone (Red Sandstone)

Arenite with Hematite/Limonite cement

Sandstone (Ferruginous)

Arenite (iron-rich)

Limestone

Calcium carbonate (CaCO3)

Sandstone (Quartzose)

Arenite (primarily SiO2)

Sandstone (Ferruginous)

Arenite (Iron-rich)

Sandstone (Weathered Pebble)

Arenite (SiO2 primarily)

Sandstone

Arenite (primarily SiO2)

Sandstone

Arenite (SiO2 based with mineral cement)

Limestone (River Pebble)

Calcium Carbonate (CaCO3)

Dalmation Stone

Peralkaline Rock (SiO2 with Arfvedsonite)

Sandstone (likely Quartzose)

Arenite (SiO2 principal mineral)