Granite Cobble
Granite (Phaneritic Igneous Rock)
Category
Browse metamorphic (altered igneous rock) specimens identified by the Rock Identifier community.
Granite Cobble
Granite (Phaneritic Igneous Rock)
Orthoclase Feldspar (or K-Feldspar)
Orthoclase (KAlSi3O8)
Quartzite
Quartzite (primarily SiO2)
Painted River Pebble (likely Basalt or Greywacke)
Aphanitic Lithic Clast with Anthropogenic Pigment coating
Scoria
Extrusive Basaltic Scoria
Milky Quartz
Silicon Dioxide (SiO2)
Garnet
Almandine (Fe3Al2(SiO4)3) or Pyrope (Mg3Al2(SiO4)3)
Quartz (Gray/Smoky Variety)
Silicon Dioxide (SiO2)
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
Rough Corundum (Sapphire/Ruby mixture)
Corundum (Aluminum Oxide, Al2O3)
Ruby
Corundum (Al2O3)
Magnetite
Iron(II,III) oxide (Fe3O4)
Potassium Feldspar
K-Feldspar (KAlSi3O8)
Sodalite
Sodalite (Na8(Al6Si6O24)Cl2)
Blue Sapphire
Corundum (Al2O3) with iron and titanium impurities
Orthoclase Feldspar
KAlSi3O8 (Potassium Aluminum Silicate)
Smoky Quartz
Silicon Dioxide (SiO2)
Pyrite
Iron Sulfide (FeS2)
Labradorite
Labradorite ((Ca, Na)(Al, Si)4O8)
Orthoclase Feldspar
Orthoclase (KAlSi3O8)
Peacock Ore
Bornite (Cu5FeS4)
Almandine Garnet
Almandine (Fe3Al2(SiO4)3)
Red Garnet (Almandine-Pyrope series)
Garnet Group, Almandine (Fe3Al2(SiO4)3) or Pyrope (Mg3Al2(SiO4)3)
Lapis Lazuli
Lapis Lazuli (A metamorphic rock primarily composed of Lazurite: (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)
Quartz Vein in Host Rock
Silicon Dioxide (SiO2) within a metamorphic matrix
Slag (Industrial Byproduct)
Artificial silicate/iron byproduct
Blue Kyanite
Kyanite (Al2SiO5)
Quartz (likely macrocrystalline variety)
Quartz (SiO₂)
Basalt (Purple-tinted scoria/vesicular variety)
Extrusive mafic igneous rock (SiO2 range 45–52%)
Basalt
Mafic Igneous Rock (composed primarily of plagioclase, pyroxene, and olivine)
Granite Cobble
Granite (Felsic Intrusive)
Serpentine (Serpentinite)
Serpentinite (complex silicate group including lizardite, chrysotile, and antigorite)
Iolite (Cordierite)
Magnesium Iron Aluminum Silicate (Mg,Fe)2Al4Si5O18
Red Garnet
Almandine (Fe3Al2(SiO4)3) or Pyrope (Mg3Al2(SiO4)3)
Serpentinite (River Pebble)
Serpentinite (complex of Antigorite, Lizardite, and Chrysotile: Mg3Si2O5(OH)4)
Serpentinite
Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)2-3(Si, Al, Fe)2O5(OH)4
Quartzite Pebble
Quartzite (SiO2)
Quartzite Pebble
Quartzite (principally SiO2)
Serpentinite
Serpentine rock (Mg,Fe,Ni,Al,Zn,Mn)3(Si,Al,Fe)2O5(OH)4
Yellow Agate
Silicon Dioxide (SiO2)
Eclogite
Eclogite (Omphacite + Almandine-Pyrope Garnet)
Mica Schist
Crystalline Schist (often containing Muscovite, Biotite, and Quartz)