Agate
Silicon Dioxide (SiO2)
Category
Browse metamorphic or igneous alteration specimens identified by the Rock Identifier community.
Agate
Silicon Dioxide (SiO2)
Agate (specifically Botswana or Lake Superior style Agate)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Emerald (Tumbled Beryl)
Beryllium Aluminum Silicate (Be3Al2Si6O18) with Chromium/Vanadium impurities
Quartzite
Quartzite (SiO2 silicon dioxide)
Dumortierite Quartz
Dumortierite (Al7BO3(SiO4)3O3 / inclusion in SiO2)
Pink Quartzite
Quartzite (SiO2 with iron oxide impurities)
Milky Quartz (with Iron Oxide staining)
Quartz (Silicon Dioxide - SiO2)
Green Aventurine (Tumbled Quartzite)
Silicon Dioxide (SiO2) with inclusions of Fuchsite
Quartzite
Quartzite (primarily SiO2)
Garnet Schist
Almandine Garnet in Mica Schist (Fe3Al2(SiO4)3)
Biotite Schist with Garnet
Garnet-Biotite Schist
Unakite
Epidotized Granite
Quartzite
Quartzite (SiO2)
Quartzite
Quartzite (primarily SiO2)
Jasper (Green)
Silicon dioxide (SiO2)
Peach Moonstone
Potassium Aluminum Silicate (KAlSi3O8); variety of Orthoclase Feldspar
Garnet (Almandine variety)
Almandine, Fe3Al2(SiO4)3
Schist
Mica Schist (contains muscovite/biotite and quartz)
Quartz Crystal Point
Silicon Dioxide (SiO2)
Kyanite
Kyanite (Al2SiO5)
Serpentinite
Serpentinite (composed primarily of Serpentine group minerals: (Mg, Fe, Ni, Al, Zn, Mn)2-3(Si, Al, Fe)2O5(OH)4)
Yellow Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
Green Aventurine
Silicon Dioxide with Fuchsite inclusions (SiO2 + K(Al,Cr)2AlSi3O10(OH)2)
Garden Quartz (Lodolite)
Quartz with inclusions (SiO2 + various inclusions such as Chlorite, Hematite, or Feldspar)
Quartz (Iron-Stained)
Silicon Dioxide (SiO2)
Agate (Geode nodule)
Cryptocrystalline Quartz (SiO2)
Quartzite
Quartzite (primarily SiO2)
Quartz (Milky/Iron-stained)
Silicon Dioxide (SiO2)
Blue Quartzite
Quartzite (silicon dioxide, SiO2)
Schist (Kyanite Schist)
Kyanite-Mica Schist (primarily Al2SiO5, KAl2(AlSi3O10)(OH)2, and SiO2)
Quartzite
Quartzite (chiefly SiO2)
River Cobble (Quartzite)
Quartzite (SiO2)
Quartzite
Quartzite
Biotite Schist
Biotite-rich Schist (K(Mg,Fe)3AlSi3O10(F,OH)2)
Rough Garnet (Almandine)
Almandine Garnet (Fe3Al2(SiO4)3)
Quartzite
Quartzite (primarily SiO2)
Fuchsite (Chrome Mica)
Cr-bearing Muscovite - K(Al,Cr)2(AlSi3O10)(OH)2
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2)
Rough Tanzanite
Zoisite (Ca2Al3(SiO4)3(OH))
Quartzite
Quartzite (SiO2)
Jasper
Jasper (Silicon Dioxide, SiO2)
Amethyst (Quartz)
Silicon Dioxide (SiO2) with Iron impurities