Amethyst
Quartz (Silicon Dioxide with iron impurities), SiO2
Category
Browse mineral (chalcedony) specimens identified by the Rock Identifier community.
Amethyst
Quartz (Silicon Dioxide with iron impurities), SiO2
Quartz (Smoky Quartz variant)
Silicon Dioxide (SiO2)
Amethyst (Quartz variety)
Silicon Dioxide (SiO2) with iron impurities
Zoisite with Ruby / Anyolite
Anyolite (Ca2Al3(SiO4)3(OH) with Chromian Zoisite and Tschermakite inclusions)
Granite
Granite (Phaneritic Acidic Igneous Rock)
Greenschist
Chlorite Schist
Feldspathic Gneiss (Granite Gneiss)
Gneiss (High-grade Regional Metamorphic Rock)
Quartz Geode Fragment
Silicon Dioxide (SiO2)
Quartz (Fieldstone/Pebble)
Silicon Dioxide (SiO2)
Indigo Gabbro
Gabbro (MaFIC intrusive rock)
Blue Lepidolite
Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2)
Quartz (River Pebble)
Silicon Dioxide (SiO2)
Gypsum (Wallboard/Drywall)
Calcium Sulfate Dihydrate (CaSO4·2H2O)
Chrysocolla in Matrix
Hydrated copper silicate - (Cu,Al)2H2Si2O5(OH)4·nH2O
Sandstone
Arenite (SiO2 based with mineral cement)
Fluorite
Calcium Fluoride (CaF2)
Granite
Granitoid (comprised of Quartz, Feldspar, and Mica)
Blue Kyanite
Kyanite (Al2SiO5)
N/A - Image is non-geological
Acrylonitrile Butadiene Styrene (ABS) or Polypropylene (PP)
Quartzite and Jasper Pebbles
Quartzite (re-crystallized Quartz) and Cryptocrystalline Quartz (SiO2)
Red Sandstone
Arenite (Ferruginous Sandstone)
Red Sandstone Pebble
Arenite with Hematite (Fe2O3) cement
Jasper containing epidote (Unakite-like)
Epidotized Jasper (SiO2 with Ca2(Al,Fe)3(SiO4)3(OH))
Garden Quartz (Phantom Quartz)
Silicon Dioxide (SiO2) with various inclusions (often Chlorite, Hematite, or Iron)
Red Sandstone
Arenite (with Iron Oxide / Hematite staining)
Lepidolite
K(Li,Al)3(Al,Si)4O10(F,OH)2 (Lithium-bearing phyllosilicate)
Sandstone (Ferruginous)
Arenite with Iron-Oxide Cement (primarily SiO2 with Fe2O3/FeOOH)
Basalt with Quartz/Zeolite Inclusions
Porphyritic Basalt (SiO2 with Aluminosilicates)
Turquoise
CuAl6(PO4)4(OH)8·4H2O (Hydrated copper and aluminum phosphate)
Malachite
Copper Carbonate Hydroxide [Cu2CO3(OH)2]
Red Sandstone
Arenite (with Iron Oxide pigmentation)
Chatoyant Quartz (Cat's Eye Quartz)
Silicon Dioxide (SiO2) with fibrous inclusions of Amphibole or Rutile
Schist
Mica Schist
Rhodochrosite
Manganese carbonate (MnCO3)
Amazonite (likely mixed with other feldspars/minerals)
Amazonite is a variety of Microcline, which is a tectosilicate mineral, formula KAISi3O8. The mixed beads could include other feldspars or quartz.
Chakra Stone Tower (Composite Multi-Mineral)
Crystalline Silicon Dioxide composite (SiO2) with various inclusions
Shale or Siltstone
Sedimentary Clastic Rock (Variable mineral composition including quartz and clay minerals)
Septarian Nodule
Septarian Concretion
Fluorite (Purple variety)
Calcium Fluoride (CaF2)
Granodiorite / Granite (Weathered)
Granodiorite
Granite
Granite (Phaneritic Igneous Rock)
Pyrite and Fluorite on Quartz (Matrix Specimen)
Iron Disulfide (FeS2) and Calcium Fluoride (CaF2) with Silicon Dioxide (SiO2)