Amethyst
Amethyst (Silicon Dioxide with iron impurities), SiO2
Category
Browse mineral and glass specimens identified by the Rock Identifier community.
Amethyst
Amethyst (Silicon Dioxide with iron impurities), SiO2
Sandstone
Clastic sedimentary rock (primarily SiO2)
Sandstone (Quartzose)
Arenite (primarily SiO2)
Sandstone (Ferruginous)
Arenite (composed primarily of SiO2 with iron oxide Fe2O3 cement)
Sandstone
Arenite
Sandstone
Clastic Sedimentary Rock (primarily SiO2)
Sandstone (with Limonite staining)
Arenite (FeOx-rich)
Quartz Pebble
Silicon Dioxide (SiO2)
Peridot (Olivine)
Olivine, (Mg, Fe)2SiO4
Amethyst
Silicon Dioxide (SiO2) with traces of Iron (Fe3+)
Prasiolite
Silicon Dioxide (SiO2) with iron impurities
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Quartz Crystal (specifically a small Clear Quartz point)
Silicon Dioxide (SiO2)
Smoky Quartz
Silicon Dioxide (SiO2)
Citrine
Silicon Dioxide (SiO2) with ferric iron impurities
Chert (and/or River Pebble)
Microcrystalline quartz (SiO2)
Chert (Flint Pebbles)
Microcrystalline quartz (SiO2)
Black Obsidian
Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)
Strawberry Quartz (Lepidocrosite/Hematite-Included Quartz)
Quartz (Silicon Dioxide) with Lepidocrosite or Hematite inclusions (SiO2 + Fe2O3 · nH2O)
Botryoidal Chalcedony (Agate/Chert Nodule)
Chalcedony (SiO2)
Milky Quartz Pebbles
Silicon Dioxide (SiO2)
Milky Quartz with Hematite inclusions
Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Lepidolite
Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2)
Orpiment
Orpiment (As2S3)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Orthoclase Feldspar
Orthoclase (KAlSi3O8)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Bull Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Milky Quartz Geode or Druzy Quartz
Silicon Dioxide (SiO2)
Smoky Quartz (Faceted Beads)
Silicon Dioxide (SiO2)
Pink Feldspar
Orthoclase Feldspar (KAlSi3O8)
Orthoclase Feldspar
Orthoclase (KAlSi3O8)
Milky Quartz
Silicon Dioxide (SiO2)
Milky Quartz (Water-worn pebble)
Quartz (Silicon Dioxide, SiO2)
Green Aventurine
Silicon dioxide with Fuscite inclusions (SiO2 + K(Al,Cr)2AlSi3O10(OH)2)
Ferruginous Quartz (Iron-stained Quartz)
Silicon Dioxide (SiO2) with Hematite/Limonite impurities
Green Aventurine
Quartzite with Fuchsite inclusions (SiO2 + K(Al,Cr)2(AlSi3O10)(OH)2)
Quartzite
Quartzite (SiO2)