Sedimentary (Secondary Mineral) Within Igneous

White Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Clear Quartz

Silicon Dioxide (SiO2)

Carnelian

Chalcedony (cryptocrystalline quartz), SiO2 (Silicon Dioxide)

Porphyritic Rhyolite (Red Porphyry)

Porphyritic Rhyolite (Felsic volcanic rock)

Quartz (Milky/Crystalline)

Silicon Dioxide (SiO2)

Turquoise

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

Sandstone (Pebble)

Arenite (primarily SiO2)

Chert (or Flint)

Chert (cryptocrystalline quartz), SiO2

Chert / Flint Nodules in Limestone

Silicon Dioxide (SiO2) within Calcium Carbonate (CaCO3)

Sandstone (Quartzose)

Arenite (SiO2 principal)

Red Jasper

Jasper (Silicon Dioxide) - SiO2

Pumice

Pumice (volcanic rock)

Sandstone (likely Siltstone variety)

Arenite / Siltstone (primary mineral SiO2)

Gneiss

Gneiss (High-grade Metamorphic Rock)

Clear Quartz

Crystalline Silicon Dioxide (SiO2)

Carnelian

Carnelian (a variety of Chalcedony, SiO2)

Picture Jasper (specifically Biggs or Deschutes variety)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Smoky Quartz

Smoky Quartz (SiO2)

Granite (likely a river or beach pebble)

Granite (a felsic intrusive igneous rock primarily composed of quartz, feldspar, and mica)

Quartz (likely) / Siliceous rock with quartz phenocrysts (if a rock fragment)

Quartz (SiO₂)

Yellow Quartzite (or Quartz River Pebble)

Silicon Dioxide (SiO2)

Banded Chert

Silicon Dioxide (SiO2)

River Pebble (Likely Chert or Fine-Grained Sandstone/Quartzite)

Siliciclastic clast (likely Chert or Quartzarenite/Quartzite pebble)

Pebble

Clast (specifically a granule or small pebble)

Milky Quartz with Iron Inclusions

Quartz (Silicon Dioxide, SiO2)

White Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Chert (Agatized Chert)

Microcrystalline Quartz (SiO2)

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

Calcium Carbonate (CaCO3)

Granite

Phaneritic Felsic Igneous Rock (primarily SiO2, Al2O3, K2O, Na2O)

Quartz (Milky/Clear)

Silicon Dioxide (SiO2)

Clear Quartz (Rock Crystal)

Quartz (Silicon Dioxide, SiO2)

Amethyst (Geode Fragment)

Silicon Dioxide (SiO2 with iron impurities)

Sandstone (Quartzose Sandstone)

Clastic sedimentary rock (primarily SiO2)

Granite (Core Sample)

Phaneritic Felsic Igneous Rock (Granite)

Lepidolite with Rubellite Tourmaline

K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2 (Lepidolite mica)

Sandstone (specifically Red Sandstone)

Arenite (primarily Quartz, SiO2)

Quartz (specifically Milky/White Quartz)

Silicon Dioxide (SiO2)

Milky Quartz

Quartz (Silicon Dioxide - SiO2)

Clear Quartz Crystal

Quartz (Silicon Dioxide, SiO2)

Chalcedony (Agate/Blue Quartzite)

Silicon Dioxide (SiO2)

Chalcedony (River Stone)

Microcrystalline Quartz (SiO2)

Chalcedony

Cryptocrystalline Quartz (SiO2)