Amethyst
Silicon dioxide with iron impurities (SiO2)
Category
Browse mineral and glass specimens identified by the Rock Identifier community.
Amethyst
Silicon dioxide with iron impurities (SiO2)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Sandstone (with Iron Staining)
Clastic Sedimentary Rock (primarily SiO2 with Fe2O3 oxides)
Quartzite with Iron Inclusions
Metamorphosed Quartz Sandstone (SiO2 with Fe2O3)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Chert / Flint
Microcrystalline or cryptocrystalline quartz (SiO2)
Quartzite Cobble
Metamorphosed Quartz Sandstone (primarily SiO2)
Chert (Cherty Limestone / Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Brecciated Chert)
Silicon Dioxide (SiO2)
Sandstone
Arenite (SiO2 with Fe2O3)
Labradorite (Feldspar)
Labradorite: (Ca,Na)(Al,Si)4O8
Sandstone
Arenite
Sandstone
Arenite (primarily SiO2, silica)
Quartzite
Quartzite (primarily SiO2)
Ferruginous Quartz (Iron-stained Quartzite)
Silicon Dioxide (SiO2) with iron oxide inclusions
Quartz Vein in Host Rock
Silicon Dioxide (SiO2) within Sedimentary/Metamorphic Matrix
Chert (and Flint variant)
Chert (SiO2)
Granodiorite / Granite
Granodiorite (containing Quartz SiO2, Plagioclase Feldspar, and Biotite)
Blue Goldstone
Aventurine Glass
Chert (Flint/Chalcedony)
Microcrystalline Quartz (SiO2)
Celestite (Celestine)
Strontium sulfate (SrSO4)
Quartz Pebble
Silicon Dioxide (SiO2)
Pyrite
Iron Sulfide (FeS2)
Agate
Silicon Dioxide (SiO2) - variety of Chalcedony
Sandstone (Quartzose)
Arenite (primarily SiO2)
Amber (Rough)
Amber (Fossilized Tree Resin, succinite)
Milky Quartz
Silicon Dioxide (SiO2)
Slag
Ferrous Slag (Amorphous calcium-magnesium-aluminum silicates)
Sandstone
Arenite (primarily composed of SiO2)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Quartzite with Garnet
Garnetiferous Quartzite (SiO2 + X3Y2(SiO4)3)
Quartz Pebble
Silicon Dioxide (SiO2)
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Blue-dyed Quartz Druzy
Silicon Dioxide (SiO2) with artificial pigment
Sandstone
Arenite (composed primarily of SiO2)
Sandstone (Quartzose Sandstone)
Arenite (SiO2 principal component)
Amethyst
Silicon Dioxide (SiO2) with Iron impurities
Quartz (Iron-stained or Ferruginous)
Silicon Dioxide (SiO2)
White Topaz
Aluminum Silicate Fluoride Hydroxide, Al2SiO4(F,OH)2
Chert (Flint variety)
Silicon Dioxide (SiO2)
Chert (Flint)
Chert (Microcrystalline Quartz, SiO2)