Carnelian
Carnelian (a variety of Chalcedony, which is a microcrystalline quartz, SiO₂)
Category
Browse sedimentary (secondary classification: cryptocrystalline quartz) specimens identified by the Rock Identifier community.
Carnelian
Carnelian (a variety of Chalcedony, which is a microcrystalline quartz, SiO₂)
Petrified Wood
Silicified Wood (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Clear Quartz
Quartz (Silicon Dioxide, SiO2)
Quartz (Druzy Quartz)
Silicon Dioxide (SiO2)
Banded Chert
Chert (a microcrystalline variety of quartz, SiO2 with minor impurities)
Quartz (Pebble)
Quartz (SiO₂)
Sandstone (Banded)
Clastic Sedimentary Rock (primarily SiO2 with Iron Oxide staining)
Quartz (likely Yellow/Orange variety, possibly Citrine or Chalcedony with iron staining)
Quartz (SiO₂)
White Quartz
Silicon Dioxide (SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)
Chalcedony (Agate Pebble)
Silicon Dioxide (SiO2)
Jasper
Jasper (Silicon Dioxide, SiO2)
Botryoidal Chalcedony
Silicon Dioxide (SiO2)
Limonite
Hydrous Iron Oxide (often Goethite FeO(OH), Lepidocrocite γ-FeO(OH), and other amorphous iron oxyhydroxides)
Quartz on Matrix
Silicon Dioxide (SiO2)
Green Aventurine
Quartzite with Fuchsite inclusions (SiO2 + K(Al,Cr)2(AlSi3O10)(OH)2)
Green Aventurine
Aventurine Quartz (SiO2 with inclusions of Fuchsite)
Ocean Jasper Mushroom
Orbicular Jasper (Silicon Dioxide, SiO2 mixed with various impurities)
Ferruginous Sandstone
Sandstone, Iron-rich
Jasper
Silicon dioxide (SiO2)
Ocean Jasper (Orbicular Jasper)
Silicon Dioxide (SiO2) with iron and magnesium inclusions
Agate Geode
Chalcedony (cryptocrystalline SiO2)
Quartz (beads)
SiO2 (Silicon Dioxide)
Carnelian Agate
Chalcedony (SiO2) with iron oxide inclusions
Chalcedony (Common Opal variant)
Silicon dioxide (SiO2) with microcrystalline structure
Dyed Agate
Silicon Dioxide with artificial pigment (SiO2)
Chert (Iron-stained)
Chert (Cryptocrystalline Silica, SiO2)
Beach Pebble (likely Quartz or Chalcedony)
Silicon Dioxide (SiO2)
Dream Amethyst (Chevron Amethyst)
Silicon Dioxide (SiO2) with iron impurities and gamma radiation exposure
Quartz Pebble
Silicon Dioxide (SiO2)
Clear Quartz
Silicon Dioxide (SiO2)
Green Aventurine
Silicon Dioxide (Quartz) with inclusions of Fuchsite (K(Al,Cr)2(AlSi3O10)(OH)2)
Chalcedony with Druzy Quartz Geode
Silicon Dioxide (SiO2)
Jasper with Quartz Druzy
Silicon Dioxide (SiO2)
Sandstone (Ferruginous)
Clastic sedimentary rock (primarily SiO2 with Fe2O3 cement)
Chalcedony (specifically Agate or Common Opal variety)
Cryptocrystalline Silica (SiO2)
Chrysocolla on Quartz/Rhyolite matrix
Hydrated copper phyllosilicate mineral: (Cu,Al)2H2Si2O5(OH)4·nH2O
Clear Quartz (Rock Crystal)
Quartz (SiO₂)
Agate
Banded Chalcedony (SiO2)
Banded Agate (specifically Lace Agate type)
Silicon Dioxide (SiO2)
Amazonite
Amazonite (KAlSi3O8 – a variety of Microcline, a Potassium Feldspar)