Amethyst
Amethyst (SiO2 with Iron impurities)
Category
Browse metamorphic rock (primarily composed of minerals) specimens identified by the Rock Identifier community.
Amethyst
Amethyst (SiO2 with Iron impurities)
Nephrite Jade
Nephrite (Ca2(Mg, Fe)5Si8O22(OH)2)
Quartzite
Quartzite (SiO2)
Rutilated Quartz
SiO2 with TiO2 inclusions
Fuchsite
Chromium-bearing Muscovite - K(Al,Cr)2(AlSi3O10)(OH)2
Coquina
Coquina (a type of limestone)
Peacock Ore (Chalcopyrite)
Chalcopyrite (CuFeS2)
Schorl (Black Tourmaline) in Matrix
Sodium Iron Aluminum Borosilicate Hydroxide (NaFe2+3Al6Si6O18(BO3)3(OH)3OH)
Schist (Graphite or Mica rich)
Crystalline Schist (often containing Muscovite, Biotite, or Graphite)
Aquamarine
Beryl (Be3Al2Si6O18 with iron impurities)
Calcite on Limestone (or Fossil)
Calcium Carbonate (CaCO3)
Citrine Geode Fragment
Citrine (Silicon Dioxide with Iron Impurities), SiO2
Limonite (Ochreous)
FeO(OH)·nH2O (Hydrated Iron Oxide)
Schist
Mica Schist (variety: Muscovite/Biotite Schist)
Sandstone
Arenite (SiO2 primarily)
Sandstone
Arenite (SiO2 primarily)
Lapis Lazuli
Na6Ca2(Al6Si6O24)(SO4,S,Cl,OH)2 (Lazurite-dominated rock)
Agate
Chalcedony (SiO2)
Quartz
Silicon Dioxide (SiO2)
Gneiss (specifically Banded Gneiss)
Gneiss
Red Sandstone
Arenite (with Iron Oxide)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Amygdaloidal Basalt
Amygdaloidal Mafic Volcanic Rock (Basalt)
Green Aventurine
Silicon Dioxide (SiO2) with inclusions of Fuchsite
Quartz Vein in River Siltstone
Crystalline Quartz (SiO2) in Siliclastic Matrix
Quartz (Clear Quartz/Rock Crystal)
Silicon Dioxide (SiO2)
Chert (Jasper variation)
Microcrystalline Quartz (SiO2)
Graphite
Graphite (Native Carbon, C)
Quartz (Milky Quartz)
Silicon Dioxide (SiO₂)
Quartz (Milky/Smoky variety)
Silicon Dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Kyanite (Purple variety)
Kyanite (Al₂SiO₅)
Yellow Calcite
Calcium Carbonate (CaCO3)
Granite
Phaneritic intrusive igneous rock (composed mainly of Quartz SiO2, Feldspar KAlSi3O8, and Biotite/Mica)
Quartz Pebble
Silicon Dioxide (SiO2)
Yellow Quartz (Citrine Quartz)
Silicon Dioxide (SiO2)
Banded Agate
Cryptocrystalline Quartz (SiO2)
Rose Quartz
Silicon Dioxide (SiO2) with traces of Titanium, Iron, or Manganese
Amazonite
Microcline (KAlSi3O8) with lead inclusions
Ferruginous Sandstone (Gerrit)
Arenite with Iron Oxide cementation
Quartz Geode
Silicon Dioxide (SiO2)
Sodalite
Sodalite (Na8(Al6Si6O24)Cl2)