Organic (Non Geological)

Quartz Vein on Matrix

Silicon Dioxide (SiO2)

Quartz Vein in Host Rock

Silicon Dioxide (SiO2) within a metamorphic matrix

Quartz (Clear Quartz)

Silicon Dioxide (SiO2)

Sandstone

Arenite (composed primarily of SiO2)

Sandstone

Arenite (SiO2 based)

Gold

Native Gold (Au)

Sandstone

Arenite (primarily SiO2)

Amethyst (as seen in jewelry)

Amethyst (Silicon Dioxide SiO2 + Fe4+)

Yellow Jasper

Silicon Dioxide (SiO2) with impure Iron inclusions

Sandstone

Arenite (primarily SiO2)

Green Aventurine

Aventurine Quartz (SiO2 with Fuchsite inclusions)

Quartzite (or Milky Quartz pebble)

Quartzite (Metamorphosed Sandstone) / Silicon Dioxide (SiO2)

Chert (Jasper/Agate variety)

Microcrystalline Quartz (SiO2)

Clear Quartz

Silicon Dioxide (SiO2)

Quartz Vein / Milky Quartz

Silicon Dioxide (SiO2)

Obsidian

Volcanic Glass (SiO2)

Gold Nugget

Native Gold (Au)

Blue Sapphire

Corundum (Al2O3 - Aluminum Oxide)

Unakite (Epidotized Granite)

Unakite (Rock composed of Epidote Ca2(Al,Fe)3(SiO4)3(OH), Orthoclase KAlSi3O8, and Quartz SiO2)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Quartz (Iron-stained)

Silicon Dioxide (SiO2)

Yellow Quartzite (Iron-Stained Quartz)

Quartzite (SiO2 with Fe-oxide impurities)

Milky Quartz

Silicon Dioxide (SiO2)

Basalt

Mafic volcanic rock (primarily plagioclase feldspar and pyroxene)

Quartz (Milky/Yellowish variety)

Silicon Dioxide (SiO2)

Quartz (Milky/Smoky variety)

Silicon Dioxide (SiO2)

Granite

Phaneritic plutonic rock (approx. 20-60% quartz, 35-90% feldspar)

Milky Quartz with Iron Staining

Quartz (Silicon Dioxide, SiO2)

Quartz (Iron-Stained or Milky Quartz)

Silicon Dioxide (SiO2)

Ferruginous Sandstone (Gozzan/Ironstone)

Arenite with Limonite/Goethite cement (FeO(OH)·nH2O)

Quartz (Milky or Cloudy Quartz)

Silicon Dioxide (SiO2)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Jasper

Jasper (Cryptocrystalline Quartz, SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Rough Quartz

Quartz (Silicon Dioxide, SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Milky Quartz

Quartz (Silicon Dioxide - SiO2)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Clear Quartz Crystal

Quartz (Silicon Dioxide, SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Basalt (Road Gravel)

Aphanitic mafic volcanic rock (various compositions of plagioclase feldspar and pyroxene)