Gneiss (Banded Gneiss)
Gneiss
Category
Browse sedimentary or igneous (host environment) specimens identified by the Rock Identifier community.
Gneiss (Banded Gneiss)
Gneiss
Chalcedony (Smoky Quartz or Agate nodule fragment)
Silicon Dioxide (SiO2)
Mica Schist
Schist (Muscovite/Biotite Schist)
Chalcedony (Agate/Quartz variety)
Cryptocrystalline Quartz (SiO2)
Mica
Phlogopite or Biotite group (KMg3(AlSi3O10)(F,OH)2 / K(Mg,Fe)3AlSi3O10(OH)2)
Prasiolite and Quartz Crystal Cluster
Quartz (SiO2); Prasiolite is a variety of Quartz
Sandstone
Arenite (SiO2 dominant)
Orange Calcite
Calcium Carbonate (CaCO3)
Orange Calcite
Calcite (Calcium Carbonate, CaCO3)
Quartz
Quartz (SiO₂)
Pumice or Tufa/Travertine
Pumice (if igneous) or Calcareous Tufa (if sedimentary)
Mixed Tumbled Gemstones (Agate, Aventurine, Pyrite, etc.)
Multiple (principally Silicon Dioxide SiO2 and Iron Disulfide FeS2)
Ferruginous Quartz (Iron-stained Quartz)
Silicon Dioxide (SiO2) with iron oxide inclusions (Limonite/Hematite)
Beryl (var. Heliodor or Aquamarine)
Beryllium Aluminum Cyclosilicate (Be3Al2Si6O18)
Quartz
Quartz (SiO₂ - Silicon Dioxide)
Glauconite
Glauconite (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2
Quartz (Pebble)
Quartz (SiO₂)
Aragonite Star Cluster
Aragonite (Calcium Carbonate, CaCO3)
Quartz (Smoky/Milky Variety)
Silicon Dioxide (SiO2)
Shale
Shale (Consolidated fine-grained clay/silt)
Biotite on Quartz
Biotite (K(Mg,Fe)3AlSi3O10(F,OH)2) and Quartz (SiO2)
Muscovite Mica
Muscovite (KAl2(AlSi3O10)(OH)2)
Moonstone with Black Tourmaline
Feldspar (KAlSi3O8) with inclusions of Schorl (NaFe3Al6(BO3)3Si6O18(OH)4)
Strawberry Quartz
Silicon Dioxide (SiO2) with Hematite or Goethite inclusions
Rhodolite Garnet
Mg3Al2(SiO4)3 - Fe3Al2(SiO4)3 (Pyrope-Almandine series)
Blue Quartz (potentially Dumortierite-included)
Silicon Dioxide (SiO2) with inclusions
Blue Sodalite
Sodalite (Na8(Al6Si6O24)Cl2)
Beryl (Aquamarine)
Beryllium Aluminum Cyclosilicate (Be3Al2Si6O18)
Muscovite Mica
KAl2(AlSi3O10)(F,OH)2
Pink Lepidolite
Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2)
Sandstone (Quartz-rich)
Arenite (SiO2)
River Stone / Pebble
Clastic Sediment (composed largely of Quartz, Feldspar, and various rock fragments)
Quartz Pebble
Silicon Dioxide (SiO2)
River Pebble (likely Quartzite or Quartz)
Quartzite (SiO2)
Bicolor Quartz Tumble
Silicon Dioxide (SiO2)
River Rock (likely Quartzite or Chert)
Quartzite (primarily SiO2)
Yellow Quartzite Pebble
Quartzite (SiO2)
Quartz (Water-worn Pebble)
Quartz (Silicon Dioxide, SiO2)
River Pebble (Quartzite/Sandstone mix)
Quartzite (primarily SiO2)
Quartzite Pebble
Metamorphosed Quartz Sandstone (SiO2)
Quartzite Cobble
Quartzite (SiO2)
Quartzite with inclusions
Metamorphosed Quartz-rich Rock (SiO2)