Quartzite
Quartzite (SiO2)
Category
Browse metamorphic (likely gneiss or schist based on texture) specimens identified by the Rock Identifier community.
Quartzite
Quartzite (SiO2)
Sandstone (Quartzose)
Arenite (primarily SiO2)
Greenstone
Chlorite schist / Meta-basalt
Microcline Feldspar
KAlSi3O8
Tumbled green aventurine (probable)
Quartzite dominated by quartz (SiO₂), with green mica/fuchsite or chlorite inclusions
Likely slate fragment
Slate; fine-grained foliated metamorphic rock, commonly quartz–mica–chlorite rich
Concretionary limestone or calcarenite pebble
Micritic limestone/calcarenite, primarily calcite (CaCO₃)
Granite
Phaneritic Plutonic Felsic Rock (primarily Quartz (SiO2), Alkali Feldspar, and Plagioclase Feldspar)
Sandstone (Ferruginous)
Arenite with Iron Oxide cement (primarily SiO2 with Fe2O3)
K-Feldspar (Potassium Feldspar)
Potassium Feldspar (KAlSi3O8)
Granite
Phaneritic plutonic felsic igneous rock
Specular Hematite (on Schist/Matrix)
Hematite (Alpha-Fe2O3)
Quartzite Pebble
Metamorphosed Quartz Sandstone (SiO2)
Mixed river stones and gravel
Polymictic alluvial clasts; individual pieces may include quartzite, granite, basalt, sandstone, limestone, and slate
Basalt
Extrusive mafic igneous rock
Quartz (Tumbled/Water-worn)
Silicon Dioxide (SiO2)
Quartzite Cobble
Quartzite (SiO2)
Quartzite
Quartzite (primarily SiO2)
Sandstone
Arenite (SiO2 primarily)
Greenstone or Epidote-rich Metamorphic Rock
Chlorite/Epidote Schist or Greenstone
Quartzite
Quartzite (SiO2)
Sandstone (Micaceous)
Arenite (composed primarily of SiO2)
Greenschist
Greenschist (chlorite-epidote schist)
Fuchsite
Chromium-rich Muscovite (K(Al,Cr)2(AlSi3O10)(OH)2)
Emerald
Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)
Red Aventurine / Orange Quartzite
Silicon Dioxide (SiO2) with hematite/goethite inclusions
Glacial Quartzite Cobble
Meta-orthoquartzite (SiO2)
Schorl (Black Tourmaline)
Sodium Iron Aluminum Borosilicate Hydroxide - NaFe2+3Al6(Si6O18)(BO3)3(OH)3OH
Black Tourmaline (Schorl)
Schorl (NaFe3Al6(BO3)3Si6O18(OH)4)
Black Tourmaline
Schorl (NaFe3Al6(BO3)3Si6O18(OH)4)
Quartz Pebble
Silicon Dioxide (SiO2)
Basalt (with Plagioclase Phenocrysts)
Porphyritic Basalt
Dark volcanic rock, likely basalt
Basalt; predominantly plagioclase feldspar, pyroxene, and minor olivine or magnetite
Sandstone
Arenite (primarily SiO2)
Granite
Granite (Plutonic Igneous Rock)
Sapphire
Corundum (Al2O3)
Ruby (Faceted)
Corundum (Al2O3 with Cr trace elements)
Aquamarine
Beryl (Be3Al2Si6O18 with iron impurities)
Raw Emerald
Beryl (Be3Al2Si6O18 with Chromium/Vanadium)
Weathered quartzite cobble
Quartzite, predominantly crystalline SiO₂
Quartzite (Ferruginous)
Metamorphosed Quartz Sandstone (SiO2 with Fe2O3 inclusions)
Quartzite
Quartzite (SiO2)