Amethyst
Amethyst (Silicon Dioxide, SiO2)
mineral
Category
Metamorphic Rock
Browse metamorphic rock specimens identified by the Rock Identifier community.
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Quartz (likely milky/rose quartz variety)
Quartz (SiO2 - Silicon Dioxide)
Mineral
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Epidote in Quartz
Quartz with Epidote inclusions (SiO2 with Ca2(Al,Fe)3(SiO4)3(OH) inclusions)
Mineral
Yellow Apatite Sphere (Polished)
Fluorapatite / Ca5(PO4)3F
mineral
Rock Crystal Quartz
Quartz (SiO₂)
Mineral
Quartz / Quartzite
Silicon Dioxide (SiO2)
Mineral / Metamorphic
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Quartz with Iron Stains
Quartz (SiO2) with iron oxide/hydroxide staining
Mineral
River Stone / Pebble
Clastic Sediment (composed largely of Quartz, Feldspar, and various rock fragments)
Mineral, Sediment
Pebble (likely Quartz or Chert)
SiO₂ (Silicon Dioxide) - referring to the likely main mineral composition, Quartz. If it's chert, the scientific name remains SiO₂ with a microcrystalline structure.
Sedimentary Rock
Orthoclase Feldspar
KAlSi3O8 (Potassium Aluminum Silicate)
Mineral
Biotite Mica
Biotite, K(Mg,Fe)3AlSi3O10(F,OH)2
mineral
Rhodonite
Manganese Silicate (Mn,Fe,Mg,Ca)SiO3
mineral
Greenstone (Greywacke or Nephrite Jade variant)
Metamorphosed mafic igneous or sedimentary rock (e.g., Actinolite-Chlorite Schist)
metamorphic
Limonite-stained Quartz / Quartzite
Silicon Dioxide (SiO2) with iron hydroxides (FeO(OH)·nH2O)
sedimentary or metamorphic
Schist
Schist
metamorphic
River Pebble (Quartzite/Siltstone mixture)
Silicon Dioxide (SiO2) mixture with varied clastic minerals
sedimentary/metamorphic
Quartz
Quartz (SiO₂)
Mineral
Brecciated Limestone or Marble Pebble
Breccia / Calcite (CaCO3)
Sedimentary / Metamorphic
River Stone (Quartzite/Siltstone mixture)
Silicon Dioxide (SiO2) based metamorphosed sandstone
metamorphic or sedimentary
Lapis Lazuli
Lapis Lazuli (Complex rock containing Sodalite, Lazurite, Calcite, and Pyrite)
metamorphic
Veined Quartz
SiO2 (Silicon Dioxide)
Mineral
Rough Emerald
Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)
mineral
Graphite
Graphite (Carbon, C)
Mineral
Agate
Agate (Cryptocrystalline Variety of Quartz, SiO2)
Mineral
Yellow Quartz (Citrine/Yellow Jasper mix)
Silicon Dioxide (SiO2) with iron oxide inclusions
mineral
River Cobble (likely Quartzite or Limestone)
SiO2 (Quartzite dominant) or CaCO3 (Limestone dominant)
metamorphic or sedimentary
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Jasper and Quartz River Cobble
Silicon Dioxide (SiO2) with Hematite inclusions
Sedimentary / Metamorphic
Garnet
Garnet Group (complex nesosilicates with general formula X3Y2(SiO4)3, where X can be Ca, Mg, Fe2+, Mn2+ and Y can be Al, Fe3+, Cr3+, V3+)
Mineral
Serpentine
Serpentine Group Minerals (e.g., Antigorite, Chrysotile, Lizardite)
Mineral, often found as a rock
Pyrite in Quartz
Iron Sulfide (FeS2) in Silicon Dioxide (SiO2)
mineral
Epidote (Unakite variety)
Epidosite (Metasomatic rock containing Ca2(Al,Fe)3(SiO4)3(OH))
metamorphic
Garnet Beads
Garnet Group (complex nesosilicates, e.g., Almandine Fe3Al2(SiO4)3)
Mineral
Serpentine
Serpentinite (a rock composed primarily of serpentine minerals like antigorite, chrysotile, and lizardite; general formula (Mg, Fe)3Si2O5(OH)4)
metamorphic
Ruby
Corundum (Al2O3 with chromium impurities)
mineral
Earth
Terra / Earth
igneous, sedimentary, and metamorphic
Quartz (Rock Crystal) with minor impurities
Quartz (SiO2)
Mineral
Blue Dumortierite in Quartz
Al7(BO3)(SiO4)3O3 (Dumortierite)
mineral
Lapis Lazuli
Na6Ca2(Al6Si6O24)(SO4,S,Cl,OH)2 (Lazurite-dominated rock)
metamorphic