Pegmatitic Granite
Granite (Alkali-feldspar granite) with Quartz and Orthoclase
Category
Browse industrial byproduct (often mistaken for obsidian or mineral) specimens identified by the Rock Identifier community.
Pegmatitic Granite
Granite (Alkali-feldspar granite) with Quartz and Orthoclase
Optical Calcite (Iceland Spar)
Calcite (Calcium Carbonate, CaCO3)
Chrysocolla
Chrysocolla: Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O
Optical Calcite (Iceland Spar)
Calcium Carbonate (CaCO3)
Lepidolite
Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2)
Sandstone (Quartz Arenite)
Sandstone (dominated by SiO2 quartz grains)
Breciated Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
Gold Nugget / Gold-bearing Quartz
Native Gold (Au)
Sandstone (Quartzose Sandstone)
Arenite (primarily SiO2)
Pyrite
Iron Sulfide (FeS2)
Blue Calcite
Calcium Carbonate (CaCO3)
Pink Tourmaline (Rubellite)
Rb:Na(Li,Al)3Al6(BO3)3Si6O18(OH)4 (Elbaite variety)
Hematite
Iron(III) oxide (Fe2O3)
Magnetite / Iron Ore
Magnetite (Fe3O4)
Orange Calcite
Calcium Carbonate (CaCO3)
Selenite (Gypsum)
Hydrous calcium sulfate (CaSO4·2H2O)
Psilomelane (Manganese Ore)
Psilomelane (Ba,H2O)2Mn5O10
Hematite
Iron(III) oxide (Fe2O3)
Turquoise (possible Dyed Magnesite/Howlite)
CuAl6(PO4)4(OH)8·4H2O
Goethite (Iron Ore)
Goethite (FeO(OH))
Pyrite on Quartz
Iron Sulfide (FeS2) on Silicon Dioxide (SiO2)
Biotite (Mica)
K(Mg,Fe)3AlSi3O10(OH,F)2
Pumice or Tufa/Travertine
Pumice (if igneous) or Calcareous Tufa (if sedimentary)
Honeycomb Calcite
Calcite (Calcium Carbonate, CaCO3)
Granite
Granite
Lepidolite
K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2 (Lithium-bearing Phyllosilicate)
Quartz with Arsenopyrite
Silicon Dioxide (SiO2) with Iron Arsenic Sulfide (FeAsS)
Granite (weathered/river-tumbled)
Granite (Plutonic Igneous Rock)
Quartz (Milky/Common)
Silicon Dioxide (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Quartz in Matrix (possibly Basalt or Siltstone host)
Silicon Dioxide (SiO2) in Host Rock
Quartz
Silicon Dioxide (SiO2)
Quartz (Quartzite)
Silicon Dioxide (SiO2)
Blue Apatite
Apatite - Ca5(PO4)3(F,Cl,OH)
Greenstone with Quartz Veining
Epidiorite or Metabasalt with SiO2 (Quartz) veins
Quartz / Quartzite
Silicon Dioxide (SiO2)
Quartz Pebble
Silicon dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Quartz in Matrix
Silicon Dioxide (SiO2)
Rhodonite
Manganese Silicate (Mn, Fe, Mg, Ca)SiO3
Epidosite (Epidote-rich rock)
Epidosite (consisting primarily of Epidote: {Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH))
Quartz
Silicon dioxide (SiO2)