Smoky Quartz
Silicon Dioxide (SiO2)
Category
Browse mineral on igneous rock specimens identified by the Rock Identifier community.
Smoky Quartz
Silicon Dioxide (SiO2)
Conglomerate
Conglomerate
Sandstone (likely River-tumbled Picture Sandstone)
Arenite (predominantly SiO2 with iron oxide impurities)
Quartz Pebble
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Sandstone or Mudstone with Iron Staining
Ferruginous Sandstone/Mudstone
Bauxite
Bauxite (Mixture including Gibbsite Al(OH)3, Boehmite γ-AlO(OH), and Diaspore α-AlO(OH))
Bauxite
Bauxite (Mixture of Al(OH)3, AlO(OH), and Fe2O3)
Glauconitic Sandstone (Greensand)
Glauconitic Quartz Arenite (containing Glauconite, (K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2)
Limonite (Iron Ore)
Limonite (FeO(OH)·nH2O)
Green Fluorite
Calcium Fluoride (CaF2)
Orthoclase Feldspar
Orthoclase (KAlSi3O8)
Pumice
Pumice (a highly vesicular volcanic glass)
Pumice
Pumicite
Pumice
Pumice (volcanic glass with vesicular texture)
Sandstone
Arenite (composed primarily of SiO2)
Olivine (Peridot when gem-quality)
Magnesium Iron Silicate, (Mg,Fe)2SiO4
Bauxite
AlOx(OH)3-2x (mixture of Gibbsite, Boehmite, and Diaspore)
Lapis Lazuli
Lapis Lazuli (Complex silicate rock containing Lazurite (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2, Calcite, and Pyrite)
Granite (weathered)
Felsic Intrusive Igneous Rock (composed of Quartz, Alkali Feldspar, and Plagioclase)
Pink Granite (Alkali Feldspar Granite)
Phaneritic Felsic Igneous Rock (composed primarily of KAlSi3O8, SiO2, and NaAlSi3O8)
Pink Granite
Phaneritic Plutonic Igneous Rock (composed of K-feldspar, Quartz, and Mica)
Diorite
Phaneritic Intrusive Igneous Rock (composed of Plagioclase feldspar, Hornblende, and Biotite)
Granite
Phaneritic Felsic Igneous Rock (primarily SiO2, Al2O3, K2O, Na2O)
Granite
Phaneritic Felsic Igneous Rock (composed primarily of Quartz, Feldspar, and Mica)
Yellow Calcite
Calcium Carbonate (CaCO3)
Druzy Quartz on Limestone
Silicon Dioxide (SiO2)
Shale (Beach-worn)
Laminated Pelite (primarily clay minerals and quartz)
Turquoise in Matrix
CuAl6(PO4)4(OH)8·4H2O (Hydrous phosphate of copper and aluminium)
Magnetite (Lodestone variety)
Magnetite (Iron(II,III) oxide, Fe3O4)
Porphyritic Basalt (or Porphyry)
Porphyritic Basalt (Mafic volcanic rock with phenocrysts)
Mixed Quartz and River Pebbles (Stone Collection)
Mixed assortment containing mainly Silicon Dioxide (SiO2)
Sandstone
Arenite (SiO2 predominantly)
Quartz Geode
Silicon Dioxide (SiO2)
Sandstone
Arenite (primarily SiO2)
Sandstone
Arenite
Botryoidal Quartz / Calcite Geode crust
Silicon Dioxide (SiO2) or Calcium Carbonate (CaCO3)
Sandstone
Arenite (Siliclastic Sedimentary Rock)
Banded Sandstone (Liesegang Rings)
Sedimentary Arenite (SiO2 with FeO/Fe2O3 impurities)
Olivine (Peridot)
Magnesium Iron Silicate ((Mg, Fe)2SiO4)
Unakite
Epidote-Feldspar rock
Amethyst
Silicon Dioxide (SiO2) with Iron impurities