Industrial Byproduct (Often Mistaken For Obsidian Or Mineral)

Iron-stained Quartz

Silicon Dioxide (SiO2) with Hematite/Limonite impurities

Sodalite

Na8(Al6Si6O24)Cl2 (Sodium Aluminum Silicate Chloride)

Obsidian

Volcanic glass

Obsidian

Volcanic glass (primary composition: SiO2)

Obsidian (specifically Mahogany Obsidian)

Volcanic glass (high silica content, SiO2)

Sandstone (specifically an Iron-Concretion)

Arenite with Iron Oxide (Limonite/Goethite) cementation

Obsidian

Obsidian (principally SiO2)

Snowflake Obsidian

Spherulitic Obsidian (SiO2 + impurities)

Milky Quartz

Quartz (Silicon Dioxide - SiO2)

Pyrite (Fool's Gold)

Iron Disulfide (FeS2)

Black Obsidian

Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)

Apache Tear (Obsidian)

Volcanic glass (SiO2 - Silicon Dioxide)

Lapis Lazuli

Lapis Lazuli (Primary mineral: Lazurite, (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)

Green Aventurine

Quartz variety (SiO2 with inclusions)

Mixed Tumbled Gemstones (Agate, Aventurine, Pyrite, etc.)

Multiple (principally Silicon Dioxide SiO2 and Iron Disulfide FeS2)

Industrial Diamond (Bort or Boart)

Diamond (pure Carbon, C)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Obsidian Arrowhead

Volcanic Glass (70% or more SiO2)

Ferruginous Quartz (Iron-stained Quartz)

Silicon Dioxide (SiO2) with iron oxide inclusions/staining (Limonite/Hematite)

Amazonite

Amazonite (KAlSi3O8); a green variety of Microcline feldspar

Sodalite

Sodalite (Na8(Al6Si6O24)Cl2)

Quartzite

Quartzite (SiO2)

Blue Quartzite (Blue Aventurine / Dumortierite Quartz)

Quartzite with inclusions (SiO2 with AlAl4BSi3O18)

Black Obsidian

Obsidian (Volcanic Glass)

Blue Quartzite (Aventurine)

Quartzite (primarily SiO2) with inclusions of Dumortierite or Magnesio-riebeckite

Liesegang Ring Siltstone

Siltstone with iron oxide Liesegang bands

Ironstone Concretion / Goethite Nodules

Ironstone (composed primarily of Goethite FeO(OH) and Limonite)

Black Onyx

Silicon Dioxide (SiO2) with cryptocrystalline structure

Pyrite

Pyrite (Iron Disulfide), FeS2

Silver (Sterling Silver Jewelry)

Argentum (Ag) mixed with Copper (Cu)

Diorite

Diorite (Intermediate intrusive igneous rock)

Sodalite

Sodalite - Na8(Al6Si6O24)Cl2

Sodalite

Sodalite (Na8(Al6Si6O24)Cl2)

Quartzite

Quartzite (primarily SiO2)

Quartzite Cobble

Meta-quartzite (SiO2)

Geodude

Geodude (Rock Pokémon: No. 74)

Unakite (bottom) and Sodalite (top)

Epidotized Granite (Unakite) and Sodium Aluminum Silicate Chloride (Sodalite)

Quartzite (Potentially Ferruginous)

Quartzite (SiO2)

Mahogany Obsidian

Obsidian (volcanic glass with Hematite/Magnetite inclusions)

Obsidian

Volcanic glass (no mineral formula due to amorphous structure, mostly SiO2)

Pyrite (Fool's Gold)

Iron Disulfide (FeS2)

Dendritic Siltstone (or Mudstone)

Siltstone with Manganese Oxide dendrites