Sedimentary (Cryptocrystalline Quartz)

Sandstone

Arenite

Gneiss (Cobble)

Gneiss

Quartz (specifically Milky or Clear Quartz)

Silicon Dioxide (SiO2)

Conglomerate

Conglomerate (clastic sedimentary rock)

Quartz / Quartzite

Silicon Dioxide (SiO2)

Gneiss

Gneiss

Clear Quartz

Silicon Dioxide (SiO2)

Clear Quartz

Silicon Dioxide (SiO2)

Ferruginous Sandstone (Ironstone)

Arenite with Limonite/Goethite cement

Granular Sandstone

Arenite (variable composition, primarily SiO2)

Rough Quartz (Alluvial Pebbles)

Silicon Dioxide (SiO2)

Quartz (Clear Quartz/Rock Crystal)

Silicon Dioxide (SiO2)

Graywacke (Sandstone)

Graywacke Sandstone

Sandstone with Quartz Vein

Arenite with Quartz (SiO2) Infilling

Banded Calcite (often marketed as 'Mexican Onyx')

Calcite (Calcium Carbonate, CaCO3)

Chert (Polished River Pebble)

Chert (SiO2)

Red Jasper

Silicon Dioxide with Iron Oxide inclusions (SiO2 + Fe2O3)

Red Sandstone

Clastic sedimentary rock (primarily SiO2 with Fe2O3)

Red Sandstone

Arenite (with Iron Oxide pigmentation)

Jasper

Silicon dioxide (SiO2) with impurities

Zebra Stone (Banded Chert or Limestone)

Silicon Dioxide (SiO2) with Calcium Carbonate (CaCO3) inclusions

Quartz Druze on Matrix

Silicon Dioxide (SiO2)

Orange Calcite

Calcite (Calcium Carbonate, CaCO3)

Gneiss

Gneiss (High-grade metamorphic rock)

Quartzite Pebble (River Rock)

Quartzite (mainly SiO2)

Banded Calcite (often sold as 'Mexican Onyx' or 'Green Onyx')

Calcite (Calcium Carbonate, CaCO3)

Orange Quartz (or Tumbled Carnelian)

Silicon Dioxide (SiO2) with iron oxide inclusions

Limonitic Sandstone with Inclusion

Limonitic Quartz Sandstone (primarily SiO2 with FeO(OH)·nH2O)

Chert (Arrowhead Artifact)

Chert (SiO2)

Fossiliferous Chert with Brachiopod Impression

Chert (SiO2) containing Brachiopoda fossil remains

Sandstone (Ferruginous)

Arenite (primarily SiO2 with Fe2O3 staining)

Clear Quartz Crystal

Quartz (Silicon Dioxide - SiO2)

Dalmatian Stone (often misnamed Dalmatian Jasper)

Aplite (with hornblende/arfvedsonite inclusions)

Quartzite (River Stone)

Quartzite (mainly SiO2 with iron oxide staining)

Herkimer Diamond (Quartz Crystal)

Silicon Dioxide (SiO2)

Quartzite / Sandstone / Chert Mix

Silicon Dioxide (SiO2)

Quartzite (Rounded Pebble)

Quartzite (predominantly SiO2)

Chert (River Pebble)

Chert (Microcrystalline Quartz, SiO2)

Jasper and Chert Conglomerate

Ferruginous Microcrystalline Quartz (SiO2)

Sandstone

Arenite (primarily Quartz SiO2)

Jasper (Red/Brown Variety)

Jasper (Microcrystalline Quartz, SiO2)

Chert (Flint)

Chert (Microcrystalline Quartz, SiO2)