Schorl (Black Tourmaline) in Pegmatite
Sodium Iron Aluminum Borosilicate (NaFe3Al6(BO3)3Si6O18(OH)4)
Category
Browse industrial byproduct (often confused with igneous rocks or meteorites) specimens identified by the Rock Identifier community.
Schorl (Black Tourmaline) in Pegmatite
Sodium Iron Aluminum Borosilicate (NaFe3Al6(BO3)3Si6O18(OH)4)
Milky Quartz Pebble
Quartz (Silicon Dioxide - SiO2)
Basalt
Basalt (Mafic volcanic rock, primarily Plagioclase and Pyroxene)
Milky Quartz
Silicon Dioxide (SiO2)
Quartzite Pebble
Quartzite (mostly SiO2)
Quartzite
Quartzite (SiO2)
Garnet (likely Almandine)
Almandine - Fe3Al2(SiO4)3
Quartzite River Pebbles
Quartzite (primarily SiO2)
Gneiss
Gneiss
Epidote
Epidote ({Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH))
Labradorite
Labradorite (Plagioclase Feldspar Series) - (Ca, Na)(Al, Si)4O8
Pyrite (on the right) and Magnetite or Hematite (on the left)
Iron Sulfide (FeS2) and Iron Oxide (Fe3O4 or Fe2O3)
Vanadinite
Lead Chlorovanadate, Pb5(VO4)3Cl
Green Fluorite
Calcium Fluoride (CaF2)
Granite
Granite (a common rock name, not a single mineral species, composed primarily of quartz, feldspar, and mica/amphibole)
Sandstone (with cross-bedding)
Arenite (composed primarily of Quartz: SiO2)
Chalcedony (Botryoidal or Tumbled)
Chalcedony (SiO₂)
Schist
Mica Schist
Orange Quartz (Citrine Quartz variety)
Silicon Dioxide (SiO2)
Rough Ruby (Corundum) in Zoisite Matrix
Al2O3 (Aluminum Oxide) with Ca2Al3(SiO4)3(OH)
Ironstone (likely Limonite or Goethite)
Ferruginous sedimentary rock (FeO(OH)·nH2O)
Bismuth
Bismuth (Bi)
Quartzite
Quartzite (primarily SiO2)
Labradorite
Labradorite (a calcium-enriched sodic plagioclase feldspar mineral - (Ca, Na)(Al, Si)4O8)
Pyrite
Iron Sulfide (FeS2)
Potassium Feldspar (Orthoclase)
KAlSi3O8
Biotite (Mica)
K(Mg,Fe)3AlSi3O10(OH,F)2
Pumice
Vesicular Rhyolite or Dacite
Quartz
Quartz (SiO₂)
Limonite (Iron Ore)
FeO(OH)·nH2O (Hydrous ferric oxide)
Quartz Vein in Host Rock
Silicon Dioxide (SiO2) within Matrix
Orange Calcite
Calcium Carbonate (CaCO3)
Pyrite
Iron Sulfide (FeS2)
Rose Quartz
Silicon Dioxide (SiO2) with traces of titanium, iron, or manganese
Gneiss
Gneiss (High-grade Metamorphic Rock)
Yellow Chalcedony (common opal or chert variant)
Silicon Dioxide (SiO2)
Orange Calcite
Calcium Carbonate (CaCO3)
Gneiss
Gneiss
Arfvedsonite in Quartz (also labeled as Astrophyllite or Nuummite by collectors)
[Na][Na2][Mg4Fe2+](Si8O22)(OH)2 in SiO2
Optical Calcite (Iceland Spar)
Calcite (Calcium Carbonate, CaCO3)
Yellow Quartz (Citrine Quartzite)
Silicon Dioxide (SiO2)
Labradorite
Labradorite ((Ca, Na)(Al, Si)4O8)