Mahogany Obsidian
Volcanic Glass with Hematite or Magnetite (SiO2 + Fe2O3)
Category
Browse mineral and glass specimens identified by the Rock Identifier community.
Mahogany Obsidian
Volcanic Glass with Hematite or Magnetite (SiO2 + Fe2O3)
Milky Quartz
Silicon Dioxide (SiO2)
Orthoclase Feldspar
KAlSi3O8 (Potassium Aluminum Silicate)
Sandstone (Ferruginous)
Arenite with Iron-Oxide Cement
Sandstone
Arenite (primarily SiO2)
Pyrite
Iron Sulfide (FeS2)
Sandstone or Quartzite
Arenite (if sedimentary) / Quartzite (if metamorphic)
Clear Quartz
Silicon dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Quartz (Chalcedony/Agate nodule)
Silicon dioxide (SiO2)
Citrine
Silicon Dioxide (SiO2)
Snowflake Obsidian
Volcanic glass with Cristobalite inclusions (70–75% SiO2)
Quartz (Iron-stained)
Silicon Dioxide (SiO2)
Sandstone
Arenite (SiO2 principal component)
Sandstone
Arenite (SiO2 predominantly)
Sandstone
Arenite
Sandstone
Sedimentary Rock (Quartz arenite / Lithic sandstone)
Quartz (Iron-stained)
Silicon Dioxide (SiO2)
Green Aventurine
Aventurine Quartz (SiO2 with Fuchsite inclusions)
Green Aventurine
SiO2 (Silicon Dioxide) with Fuchsite inclusions
Green Aventurine (Double-Terminated Wand)
Silicon Dioxide (SiO2) containing Fuchsite (Chromium-rich Muscovite Mica)
Aventurine
Quartz with fuchsite inclusions (SiO2)
Quartz
Silicon Dioxide (SiO2)
Red Sandstone
Arenite with iron oxide (Hematite) cement
Sandstone
Arenite (SiO2 primarily)
Quartz Pebble
Silicon Dioxide (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Milky Quartz or Calcite Pebble
Silicon Dioxide (SiO2) or Calcium Carbonate (CaCO3)
Milky Quartz
Crystalline Silicon Dioxide (SiO2)
Lepidolite
Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2)
Lepidolite
Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2)
Quartz (Iron-stained Pebble)
Silicon Dioxide (SiO2)
Libyan Desert Glass
Tektite (high-silica impact glass), SiO2
Milky Quartz
Silicon Dioxide (SiO2)
White Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
Green Aventurine
Silicon dioxide (SiO2) with fuchsite inclusions
Milky Quartz Pebble with Matrix
Silicon Dioxide (SiO2)
Clear Quartz
Silicon Dioxide (SiO2)
Quartz Geode with Calcite
Silicon Dioxide (SiO2) with Calcium Carbonate (CaCO3)
Milky quartz
Quartz (silicon dioxide, SiO₂)
Amethyst
Silicon Dioxide (SiO2) with iron impurities