Mineral And Glass

Milky Quartz

Silicon Dioxide (SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Smoky Quartz (Rough)

Silicon Dioxide (SiO2)

Amethyst on Basalt

Silicon dioxide (SiO2) with trace Iron

Fluorite

Calcium Fluoride (CaF2)

Green Aventurine

Quartzite (variety Aventurine) with Fuchsite inclusions (K(Al,Cr)2(AlSi3O10)(OH)2)

Sandstone (specifically Lithic or Quartz Arenite)

Arenite (composed primarily of SiO2)

Quartz (Smoky Quartz variant)

Silicon Dioxide (SiO2)

Quartz (Smoky/Granular variety)

Silicon Dioxide (SiO2)

Quartz pebble

Silicon dioxide (SiO2)

Sandstone

Arenite (predominantly SiO2)

Sandstone (likely Graywacke or Arkose)

Arenite

Sandstone Pebble

Arenite (SiO2 based)

Sandstone (Quartzose)

Arenite (primarily SiO2)

Sandstone (Quartzose)

Arenite (primarily SiO2)

Sandstone

Arenite (primarily SiO2)

Sandstone

Arenite (SiO2 principal)

Likely weathered quartz-bearing rock (uncertain identification)

Possibly quartz-rich granite or granitic aplite; exact identification requires a clearer, larger image and tests

Clear Quartz Crystal

Silicon Dioxide (SiO2)

Milky quartz with dark host-rock inclusions

Quartz (SiO₂), likely in a granitic or metamorphic matrix

Tumbled green aventurine

Quartzite dominated by quartz (SiO₂), with green mica/fuchsite inclusions

Green Aventurine

Silicon Dioxide (SiO2) with Fuchsite inclusions (K(Al,Cr)2AlSi3O10(OH)2)

Milky Quartz with Iron Oxides

Silicon Dioxide (SiO2) with Fe2O3 inclusions

Clear Quartz

Silicon Dioxide (SiO2)

Black Obsidian with white veins

Volcanic Glass (70–75% SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Tumbled reddish sandstone pebble

Quartz-rich sandstone, likely ferruginous arkose or quartz arenite

Likely calcite or quartz fragment

Uncertain from image; calcite (CaCO₃) is the leading possibility, with quartz (SiO₂) another possibility

Quartz

Silicon Dioxide (SiO2)

Ferruginous Quartz

Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions

Chert (Flint with Iron Staining)

Silicon Dioxide (SiO2)

Rock Crystal Quartz

Silicon Dioxide (SiO2)

Polished mahogany obsidian (likely)

Volcanic glass; primarily silica-rich rhyolitic glass (SiO₂), with iron oxides

Milky Quartz Pebble

Crystalline Silicon Dioxide (SiO2)

Rose Quartz

Rose Quartz (SiO2 with traces of Titanium, Iron, or Manganese)

Quartz

Silicon Dioxide (SiO2)

Unidentified translucent mineral fragment, possibly calcite

Calcite (calcium carbonate, CaCO₃), tentative identification

Quartz crystal pendant

Quartz (silicon dioxide, SiO₂), likely rock crystal or milky quartz

Sandstone

Arenite (SiO2 principal)

Quartz fragment

Silicon Dioxide (SiO2)

Blue Quartz (or Blue Aventurine)

Silicon Dioxide (SiO2) with inclusions (typically Crocidolite or Dumortierite)