Mahogany Obsidian
Obsidian (Volcanic Glass) with Hematite or Magnetite inclusions, SiO2 (Silicon Dioxide)
Category
Browse mineral and glass specimens identified by the Rock Identifier community.
Mahogany Obsidian
Obsidian (Volcanic Glass) with Hematite or Magnetite inclusions, SiO2 (Silicon Dioxide)
Chert / Chalcedony
Silicon Dioxide (SiO2)
Sandstone
Arenite (primarily SiO2)
Sandstone
Arenite (primarily SiO2)
Sandstone
Arenite (composed primarily of SiO2)
Sandstone (with banding/weathering)
Clastic Sedimentary Rock (primarily SiO2)
Sandstone (Quartz-rich)
Arenite (SiO2 based)
Dream Amethyst (Chevron Amethyst)
Silicon Dioxide with Iron impurities (SiO2)
Fluorite (specifically Rainbow Fluorite or Purple Fluorite)
Calcium Fluoride (CaF2)
Smoky Quartz (Tumbled)
Smoky Quartz (SiO2 - Silicon Dioxide)
Rose Quartz
Silicon Dioxide with trace inclusions (SiO2)
Amethyst
Silicon dioxide with iron impurities (SiO2 + Fe3+)
Cloudy Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Blue Celestite (Celestine) Cluster
Strontium sulfate (SrSO4)
Milky Quartz (Common Quartz/Crystalline Quartz)
Quartz (Silicon Dioxide, SiO2)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Beach Quartz Pebble
Quartz (Silica - SiO2)
Lepidolite Polished Point
Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2)
Quartz Vein in Host Rock
Silicon Dioxide (SiO2)
Rough Quartz (or Quartzite pebble)
Silicon Dioxide (SiO2)
Pyrite (on Quartz matrix)
Iron Sulfide (FeS2)
Ferruginous Quartz (Stained Quartz)
Silicon Dioxide (SiO2) with secondary Iron Oxide inclusions (Limonite/Hematite)
Chert (variations include Flint or Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Lepidolite
Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2)
Milky Quartz (Water-worn Pebble)
Silicon Dioxide (SiO2)
Smoky Quartz
SiO2 (Silicon Dioxide)
Rose Quartz
Silicon Dioxide (SiO2)
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
Lepidolite and Rubellite (Pink Tourmaline) in Quartz
K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2 (Lepidolite) and Na(Li,Al)3Al6(BO3)3Si6O18(OH)4 (Elbaite/Pink Tourmaline)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Smoky Quartz
Silicon Dioxide (SiO₂)
Chalcedony (Desert Rose or Botryoidal Chalcedony)
Silicon Dioxide (SiO2)
Red Jasper
Silicon Dioxide (SiO2) with Hematite inclusions
Banded Agate (Tumbled)
Agate (Silicon Dioxide, SiO2 - Cryptocrystalline Quartz)
Carnelian Agate
Carnelian (Silicon Dioxide, SiO2)
Sapphire
Corundum (Al2O3)
Chalcedony (Agate/Chert variety)
Silicon Dioxide (SiO₂)
Yellow Quartz (Chalcedony/Agate)
Silicon Dioxide (SiO2)
Red Garnet (likely Almandine or Pyrope)
Garnet group: X3Y2(SiO4)3 (e.g., Almandine: Fe3Al2Si3O12)
Milky Quartz
Silicon Dioxide (SiO2)
Chalcedony (Agate/Carnelian precursor)
Chalcedony (Silicon Dioxide, SiO2)