Agate
Silicon dioxide (Chalcedony), SiO2
Category
Browse industrial byproduct (anthropogenic rock) specimens identified by the Rock Identifier community.
Agate
Silicon dioxide (Chalcedony), SiO2
Coal
Bituminous Coal / Anthracite
Quartz with Feldspar and Mica (Pegmatite Fragment)
Granitic Pegmatite
Quartz Crystal Fragment
Silicon Dioxide (SiO2)
Quartz (Smoky Quartz / Calcite)
SiO2 (Silicon Dioxide)
Quartzite Pebble
Metamorphosed Silicon Dioxide (SiO2)
Garnet (Almandine)
Almandine (Fe3Al2(SiO4)3)
Quartzite Cobble
Quartzite (SiO2)
Quartzite Pebble
SiO2 (Silicon Dioxide)
Red Sandstone
Ferruginous Sandstone (SiO2 dominated with Fe2O3)
Cubic Zirconia (Jewelry Setting)
Cubic Zirconia (ZrO2)
Black Tourmaline (Schorl)
Schorl (NaFe3Al6(BO3)3Si6O18(OH)4)
Diamond (or Diamond Simulant)
Carbon (C)
Smoky Quartz (Rough)
Silicon Dioxide (SiO2)
Limestone
Calcium Carbonate (CaCO3)
Quartz Pebble
Silicon Dioxide (SiO2)
Quartz with Iron Staining
Crystalline Silicon Dioxide (SiO2)
Pink Garnet (likely Almandine or Rhodolite)
Garnet Group (Fe3Al2(SiO4)3 to Mg3Al2(SiO4)3)
Diamond
C (Carbon)
White Marble
Recrystallized Calcite (CaCO3)
River Quartz Cobble
Silicon Dioxide (SiO2)
Yellow Quartz (Citrine or Iron-stained Quartz)
Silicon Dioxide (SiO2)
Planet Earth
Gaia (Silicate Terrestrial Planet)
Marble
Recrystallized Calcite (CaCO3)
Sandstone
Arenite (SiO2 principal composition)
Vanadinite on Matrix
Vanadinite (Pb5(VO4)3Cl)
Garnet
Garnet Group (Silicate Minerals), formula varies e.g., Alm: Fe3Al2(SiO4)3
Fluorite, Sodalite, and Rose Quartz collection
Calcium Fluoride (CaF2), Sodium Aluminum Silicate with Chlorine (Na8(Al6Si6O24)Cl2), Silicon Dioxide (SiO2)
Ruby (varieties of Corundum)
Aluminum oxide (Al2O3) with Chromium traces
Quartz Pebble (Chalcedony/Agate variety)
Silicon Dioxide (SiO2)
Red Garnet (likely Almandine or Pyrope)
Garnet group: X3Y2(SiO4)3 (e.g., Almandine: Fe3Al2Si3O12)
Blue Sapphire (likely costume glass imitation)
Corundum (Al2O3) with iron/titanium impurities
Quartz Pebble
Silicon Dioxide (SiO2)
Quartz Geode (Water-worn)
Silicon Dioxide (SiO2)
Marble
Recrystallized Calcite (CaCO3)
Gold in Quartz
Hydrothermal Quartz with Native Gold (SiO2 with Au)
Desert Rose
Gypsum (CaSO4·2H2O) or Barite (BaSO4)
Quartz with Iron Oxide Staining
Silicon Dioxide (SiO2)
Quartz Pebble with Iron Staining
Silicon Dioxide (SiO2) with Hematite/Limonite matrix
Lepidolite
K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2
Mica in Quartz Host
Muscovite (KAl2(AlSi3O10)(OH)2) in Quartz (SiO2)
Kaolinite (China Clay)
Kaolinite (Al2Si2O5(OH)4)