Gneiss (Granitic Gneiss)
Gneiss
Category
Browse sedimentary rock (possibly composed of various minerals) specimens identified by the Rock Identifier community.
Gneiss (Granitic Gneiss)
Gneiss
Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Sandstone
Arenite (primarily Quartz, SiO2)
Crystalline Quartz (Rough)
Quartz (Silicon Dioxide, SiO2)
Lapis Lazuli
Lapis Lazuli (A metamorphic rock primarily composed of Lazurite: (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2, along with Calcite and Pyrite)
Emerald
Beryl (Be3Al2Si6O18) with trace amounts of Chromium and/or Vanadium
Quartz Vein in Host Rock (clastic sediment)
Silicon Dioxide (SiO2) in matrix
Pink Anthracite Coal (dyed)
Anthracite Coal (Artificially Colored)
Chalcedony (Agate/Quartz variety)
Cryptocrystalline Quartz (SiO2)
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Fe2O3 inclusions)
Quartz Geode
Silicon Dioxide (SiO2)
Quartz / Rock Crystal
Silicon Dioxide (SiO2)
Granite (Pink/Red Orthoclase variety)
Phaneritic Plutonic Felsic Rock (SiO2, KAlSi3O8, NaAlSi3O8, CaAl2Si2O8)
Diorite
Diorite (an intrusive igneous rock)
Diorite
Intermediate plutonic igneous rock
Carnelian
Carnelian (SiO2 with Iron Oxide impurities)
Pink Granite
Phaneritic Felsic Igneous Plutonic Rock
Granite
Granite (Felsic Intrusive Igneous Rock)
Granite
Granite (High-silica plutonic rock)
Milky Quartz
Quartz (Silicon Dioxide - SiO2)
Quartz Druse (on Chalcedony/Agate base)
Silicon Dioxide (SiO2)
Carnelian Agate
Silicon Dioxide (SiO2) - variety of Chalcedony
Yellow Jasper
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Sandstone (specifically an Iron-Concretion)
Arenite with Iron Oxide (Limonite/Goethite) cementation
Green Aventurine
Quartzite with Fuchsite inclusions (SiO2 + K(Al,Cr)2(AlSi3O10)(OH)2)
Blue Chalcedony
Microcrystalline Quartz (SiO2)
Chalcedony (Agate)
Silicon Dioxide (SiO2)
Diorite
Diorite (Intermediate intrusive igneous rock)
Yellow Quartz (Citrine/Lemon Quartz)
Silicon Dioxide (SiO2)
Quartz (Pale Rose or Milky Variety)
Silicon Dioxide (SiO2)
Sandstone (Quartz-rich Pebble)
Arenite (primarily SiO2)
Granite Pegmatite
Coarse-grained Granite (SiO2 - Aluminum and Alkalies)
Limestone
Calcium Carbonate (CaCO3)
Granodiorite
Granodiorite (Na,Ca)(Si,Al)4O8
Basalt with Iron Oxidation
Amygdaloidal Basalt (silicate rock primarily plagioclase, pyroxene, and olivine)
Concrete
Anthropogenic Sedimentary Conglomerate (Cement mixture: typically Ca2SiO4, Ca3SiO5, Ca3Al2O6)
Druzy Quartz
Silicon Dioxide (SiO2)
Sandstone
Arenite (SiO2 primarily)
Jasper
Silicon dioxide (SiO2)
Ocean Jasper
Silicon dioxide with impurities (SiO2 + impurities)
Sandstone (Red)
Arenite (SiO2 with Fe2O3)