Mineral (Impactite)

Yellow Jasper with Dendritic Inclusions

Silicon Dioxide (SiO2) with Manganese/Iron Oxide inclusions

Bauxite

Bauxite (mixture of Hydrous Aluminum Oxides)

Barite (Desert Rose or Cockscomb variety)

Barium Sulfate (BaSO4)

Obsidian

Volcanic Glass (Primary composition: SiO2 - Silicon Dioxide)

Igneous

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Limonite (Ironstone Concretion)

Limonite (Hydrous ferric oxide mixture, FeO(OH)·nH2O)

Tiger's Eye

Pseudomorph of quartz after crocidolite (SiO2 with iron inclusions)

Limonite (Iron Ore)

FeO(OH)·nH2O (Hydrated iron(III) oxide-hydroxide)

Quartz (Tumbled/Polished Pebble)

Silicon Dioxide (SiO2)

Magnetite (likely in Hematite or Ironstone)

Magnetite (Fe3O4)

Lapis Lazuli

Lapis Lazuli (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2

Quartz (Iron-stained)

Silicon Dioxide (SiO2)

Clear Quartz

Silicon Dioxide (SiO2)

Clear Quartz Crystal Cluster

Silicon Dioxide (SiO2)

Green Fluorite

Calcium Fluoride (CaF2)

Bauxite

Bauxite (Al(OH)3, γ-AlO(OH), and α-AlO(OH))

Diamond (or Cubic Zirconia simulant)

Carbon (C) - Diamond / Zirconium dioxide (ZrO2) - CZ

Milky Quartz

Silicon Dioxide (SiO2)

Milky Quartz Pebble

Crystalline Silicon Dioxide (SiO2)

Feldspar (Orthoclase)

Potassium Feldspar (KAlSi3O8)

Clear Quartz

Silicon Dioxide (SiO2)

Lapis Lazuli

Lazurite-dominant Metamorphic Rock (complex aluminosilicate)

Jet

Lignite (Anthracite-grade compact coal)

Rose Quartz

Silicon Dioxide (SiO2)

Rose Quartz

Silicon Dioxide (SiO2)

Clear Quartz

Silicon Dioxide (SiO2)

Quartz Geode (Water-worn)

Silicon Dioxide (SiO2)

Red Jasper

Silicon Dioxide (SiO2) with Hematite (Fe2O3)

Agatized Petrified Wood

Silicon Dioxide (SiO2) - Chalcedony pseudomorph after Wood

Pyrite

Iron Sulfide (FeS2)

Jadeite and Assorted Corundum (Ruby/Sapphire) / Beryl (Emerald)

Jadeite (NaAlSi2O6), Ruby/Sapphire (Al2O3), Emerald (Be3Al2(SiO3)6)

Man-made byproduct (often mistaken for Obsidian or Emerald)

Cullet Glass (Industrial Slag Glass)

Amorphous Silica (SiO2) with metallic oxide impurities

Basalt River Stone

Basalt

Granite

Granite (Mainly Quartz, Feldspar, and Mica/Amphibole)

Granite

Granite (Mainly Quartz, Feldspar, and Mica/Amphibole)

Quartzite (Iron-stained)

Quartzite (primarily SiO2)

Granite

Granite (Alkali-feldspar, Quartz, and Plagioclase composition)

Granite

Phaneritic Felsic Igneous Rock (primarily Quartz, Feldspar, and Mica)

River Stone (likely Mudstone or Siltstone)

Lutite (Clastic sedimentary rock composed of clay and silt-sized particles)