Agate
Agate (a cryptocrystalline variety of Quartz, SiO₂)
Category
Browse mixed (sedimentary, igneous, and metamorphic) specimens identified by the Rock Identifier community.
Agate
Agate (a cryptocrystalline variety of Quartz, SiO₂)
Jade (Nephrite or Jadeite)
Nephrite (Ca2(Mg,Fe)5Si8O22(OH)2) or Jadeite (Na(Al,Fe3+)Si2O6)
Wishing Stone (Basalt or Mudstone with Quartz/Calcite Veins)
Hydrothermally veined Basalt (SiO2/CaCO3 intrusions)
Serpentinite
Serpentinite (composed primarily of Serpentine group minerals like Antigorite, Lizardite, and Chrysotile)
Amazonite
Amazonite (KAlSi3O8, a variety of Microcline)
Rhodonite
Manganese Silicate (Mn,Fe,Mg,Ca)SiO3
Rhodonite
Rhodonite (Mn,Fe,Mg,Ca)SiO3
Black Chert
Chert (microcrystalline quartz)
Unidentified River Rock or Mudstone
N/A (Generic rock fragment)
River Pebbles (Sandstone and Quartzite)
SiO2 (Quartz) dominated clastic rocks
River Pebble (Quartzite/Siltstone mixture)
Silicon Dioxide (SiO2) mixture with varied clastic minerals
Micaceous Sandstone or Quartzite
Sandstone (lithified quartz grains, often with mica) or Quartzite (metamorphosed sandstone)
River Pebble (likely Quartzite or Chert)
Silicon Dioxide (SiO2) crystal conglomerate
Quartzite and Chert
Silicon Dioxide (SiO2)
Almandine Garnet
Almandine (Fe3Al2(SiO4)3)
Eclogite
Eclogite (Omphacite + Pyrope)
River Pebble (Basalt/Greywacke)
Weathered Basalt or Fine-Grained Greywacke
Quartzite
Quartzite
Green Aventurine
Silicon Dioxide (Quartz with Fuchsite inclusions), SiO2 + K(Al,Cr)2AlSi3O10(OH)2
Nephrite Jade
Ca2(Mg, Fe)5Si8O22(OH)2
Orthoclase Feldspar
Potassium aluminum silicate (KAlSi3O8)
Quartz vein in metamorphic rock
Crystalline Silicon Dioxide (SiO2) in Host Rock
Quartzite
Quartzite
Prehnite
Prehnite (Ca2Al2Si3O10(OH)2)
Eclogite
Eclogite (Pyrope garnet and Omphacite pyroxene)
Jadeite (Nephrite)
Ca2(Mg,Fe)5Si8O22(OH)2
Slate
Slate
Peridot (Olivine)
Olivine ((Mg,Fe)2SiO4)
Rhodonite
Rhodonite (MnSiO3)
Garnet (likely Almandine or Pyrope)
Garnet Group (e.g., Almandine: Fe3Al2(SiO4)3; Pyrope: Mg3Al2(SiO4)3)
Biotite Schist
Biotite-rich Schist [K(Mg,Fe)3AlSi3O10(F,OH)2]
Schist
Mica Schist
Milky Quartz
Silicon Dioxide (SiO2)
Quartzite with Quartz Vein
Quartzite (primarily SiO2)
Rhodonite
Manganese Silicate (Mn,Fe,Mg,Ca)SiO3
Nephrite Jade
Ca2(Mg,Fe)5Si8O22(OH)2
Fuchsite
Chrome-bearing Muscovite [K(Al,Cr)2(AlSi3O10)(OH)2]
Mica Schist
Mica Schist (predominantly Muscovite or Biotite)
Pink Opal / Peruvian Opal
Hydrated amorphous silicon dioxide (SiO2·nH2O)
Grey River Stone (Quartz-rich Quartzite/Siltstone)
Quartzite / Meta-siltstone (primarily SiO2)
Gold
Aurum (Elemental Gold, Au)
Dendritic Agate (or Dendritic Opal)
SiO2 (for Agate), SiO2·nH2O (for Opal)