Man Made Glass (Not A Natural Rock Or Mineral)

Sandstone

Arenite (primarily SiO2)

Milky Quartz

Silicon dioxide (SiO2)

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Granite

Phaneritic Igneous Rock (composed of quartz, alkali feldspar, and plagioclase)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Quartz / Milky Quartz

Silicon Dioxide (SiO2)

Clear Quartz

Silicon Dioxide (SiO2)

Chert (specifically White Chert or Novaculite)

Silicon Dioxide (SiO₂)

Obsidian

Volcanic glass (SiO2-rich extrusive igneous rock)

Limonite with Hematite

Limonite (FeO(OH)·nH2O) and Hematite (Fe2O3)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Aventurine

Silicon Dioxide (Quartz with Fuchsite inclusions) - SiO2

Sandstone (Red)

Arenite (SiO2 with Fe2O3)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Clear Quartz Sphere

Quartz (Silicon Dioxide, SiO2)

Sandstone (Ferruginous)

Arenite (primarily SiO2 with Fe2O3 staining)

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Milky Quartz (Druzy Geode fragment)

Silicon Dioxide (SiO2)

Sandstone (with Iron Staining)

Clastic sedimentary rock (primarily Quartz with Fe2O3 staining)

Sandstone

Arenite (primarily SiO2)

Ferruginous Quartz (Iron-stained Quartzite)

Silicon Dioxide (SiO2) with Hematite/Limonite impurities

White Sapphire

Corundum (Al2O3)

Pegmatite

Coarse-grained Igneous Rock (Granitic Pegmatite)

Obsidian

Volcanic Glass (Amorphous Silica)

Sandstone (Red)

Arenite (Fe2O3 heavy)

Diorite

Diorite

Sandstone (likely Quartzose Sandstone)

Arenite (SiO2 predominantly)

Sandstone

Arenite (primarily SiO2)

Quartz with Iron Staining

Silicon Dioxide (SiO2) with iron oxide impurities

Milky Quartz with Mineral Inclusions

Quartz (Silicon Dioxide - SiO2)

Black Sand (Magnetite Sand)

Magnetite (Fe3O4)

Slate

Slate (Low-grade foliated metamorphic rock)

Sandstone

Arenite (Sedimentary rock comprising sand-sized grains)

Pearl

Calcium Carbonate (primarily Aragonite and Calcite), CaCO3

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Chert / Flint

Chert (Silicon Dioxide, SiO2)

Chert (Arrowhead Artifact)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Quartzite

Quartzite (SiO2)

Quartz (Milky or Clear variety)

Silicon Dioxide (SiO2)

Pyrite (Fool's Gold)

Iron Sulfide (FeS2)

Red Jasper

Jasper (Silicon Dioxide, SiO2 with Iron Oxide impurities)

Quartz Pebble

Silicon Dioxide (SiO2)