Basalt
Mafic Igneous Rock
Category
Browse igneous or metamorphic specimens identified by the Rock Identifier community.
Basalt
Mafic Igneous Rock
Vesicular Basalt
Mafic Igneous Rock
Diorite (River Cobble)
Intrusive Igneous Diorite
Basalt with Iron Oxidation
Mafic Igneous Basalt
Schist
Mica Schist
Quartz (Milky/Iron-stained)
Silicon Dioxide (SiO2)
Kyanite (Blue or Blue-Grey)
Kyanite (Al2SiO5)
Ferruginous Quartz (Iron-stained Quartz)
Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions
Quartz Vein in Host Rock
Silicon Dioxide (SiO2)
Quartzite
Quartzite (primarily composed of SiO O₂)
Quartzite Pebble
Metamorphosed Sandstone (SiO2)
Quartzite
Quartzite (primarily SiO2)
Quartz with Hematite Inclusions
Silicon Dioxide (SiO2) with Ferric Oxide (Fe2O3)
Milky Quartz
Silicon Dioxide (SiO2)
Gneiss (specifically a Granitic Gneiss specimen)
Gneiss (high-grade metamorphic rock primarily composed of Quartz, Feldspar, and Biotite/Amphibole)
Diorite (Salt and Pepper Rock)
Diorite
Quartzite
Quartzite (primarily SiO2)
Granite
Granite
Granite
Granite (Felsic Plutonic Rock)
Dalmation Stone (Dalmation Jasper)
Peralkaline rock (primarily Feldspar and Quartz with Arfvedsonite spots)
Quartzite
Quartzite (primarily SiO2)
Sodalite
Sodalite (Na8(Al6Si6O24)Cl2)
Green Quartzite
Metamorphic rock primarily composed of Silicon Dioxide (SiO2) with mineral inclusions like fuchsite or chlorite
Banded Slate or Siltstone with Quartz/Calcite Veins
Protolith-derived Siltstone or Slate (varies based on degree of metamorphism)
Emerald
Beryl (Be₃Al₂Si₆O₁₈), specifically the green variety colored by trace amounts of chromium or vanadium.
Tiger's Eye
Tiger's Eye (a variety of Chalcedony, which is a microcrystalline quartz with fibrous inclusions of oxidized crocidolite)
Jade (Nephrite or Jadeite)
Nephrite (Ca2(Mg,Fe)5Si8O22(OH)2) or Jadeite (Na(Al,Fe3+)Si2O6)
Felsic Igneous Rock (likely Rhyolite or weathered Granite)
Felsic Volcanic/Plutonic Rock
Aquamarine and clear quartz
Aquamarine (Be3Al2Si6O18), Quartz (SiO2)
Quartz (River-worn Pebble)
Quartz (SiO2)
Blue Kyanite
Kyanite (Al2SiO5)
Graphite
Graphite (Native Carbon, C)
Rough Ruby (Corundum) in Zoisite Matrix
Al2O3 (Aluminum Oxide) with Ca2Al3(SiO4)3(OH)
Pink Quartzite
Quartzite (SiO2)
Serpentine
Serpentinite (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4
Amazonite
Microcline (KAlSi3O8) with Pb impurities
Grey Agate
Silicon Dioxide (SiO2) - variety: Agate/Chalcedony
Banded Agate
Cryptocrystalline Quartz (SiO2)
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2)
Tiger's Eye (Inlaid in a band)
SiO2 (Silicon Dioxide with Crocidolite inclusions)
Emerald in Matrix
Beryllium Aluminum Silicate (Be3Al2Si6O18) with Chromium/Vanadium impurities
Rutilated Quartz
Silicon Dioxide (SiO2) with Titanium Dioxide (TiO2) inclusions