Quartz (specifically Milky/Gray Quartz)
Silicon Dioxide (SiO2)
Category
Browse mixed (igneous, sedimentary, metamorphic, and minerals) specimens identified by the Rock Identifier community.
Quartz (specifically Milky/Gray Quartz)
Silicon Dioxide (SiO2)
Pebble (likely Sandstone or Granitic Pebble)
Clastic Sediment (or specific rock type, e.g., Arenite, Granitoid Pebble)
Green Aventurine (Green Quartzite)
Silicon Dioxide (SiO2) with inclusions of Fuchsite mica
Bloodstone (Heliotrope)
Silicon Dioxide (SiO2) with inclusions of Chlorite or Actinolite
Quartz (Milky/Vein Quartz)
Silicon Dioxide (SiO2)
Amazonite
K(AlSi3O8) - Lead-bearing Microcline (Tectosilicate)
Calcite
Calcite (CaCO3)
Quartz Vein in Host Rock
Silicon Dioxide (SiO2)
Grey Agate (Banded Chalcedony)
Agate (Silicon Dioxide - SiO2)
Marble
Marble (metamorphosed limestone or dolostone), primarily composed of calcite (CaCO3) or dolomite (CaMg(CO3)2)
Chalcedony (River Stone)
Microcrystalline Quartz (SiO2)
Yellow Chalcedony (common opal or chert variant)
Silicon Dioxide (SiO2)
Pyrite
Iron Disulfide (FeS2)
Milky Quartz
Silicon Dioxide (SiO2)
Biotite or Phlogopite Mica
K(Mg,Fe)3(AlSi3O10)(F,OH)2
Rough Garnet (Almandine)
Almandine Garnet (Fe3Al2(SiO4)3)
Fluorite
Calcium Fluoride (CaF2)
Arsenopyrite in Quartz Matrix
Arsenopyrite (FeAsS) with Quartz (SiO2)
Ferruginous Quartz
Silicon Dioxide with Iron Oxide (SiO2 + Fe2O3)
Pyrite
Pyrite (FeS2)
Clear Quartz
Quartz (Silicon Dioxide, SiO2)
Serpentinite
Serpentinite (composed primarily of Serpentine group minerals, Mg3Si2O5(OH)4)
Sapphire (Corundum variety)
Sapphire (Al₂O₃)
Banded Gneiss (River Rock/Pebble)
Gneiss (specifically a banded variety, likely a orthogneiss or paragneiss depending on parent rock)
Mica Schist
Mica Schist (Composition typically contains Muscovite: KAl2(AlSi3O10)(OH)2 or Biotite: K(Mg,Fe)3AlSi3O10(OH)2 along with Quartz and Feldspar)
Pyrite
Iron Disulfide (FeS2)
Yellow Sapphire or Citrine
Al2O3 (Corundum) or SiO2 (Quartz)
Mica Schist
Mica Schist (KAl2(AlSi3O10)(OH)2 / K(Mg,Fe)3AlSi3O10(OH)2)
Quartz Pebble
Silicon Dioxide (SiO2)
Lapis Lazuli (Lazurite crystals on Marble)
Lazurite / (Na,Ca)8[(S,Cl,SO4,OH)2|(AlSiO4)6]
Zebra Marble
Metamorphosed Alabaster/Limestone (CaCO3)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Lapis Lazuli
Lapis Lazuli (a rock composed primarily of Lazurite (Na,Ca)₈[(S,Cl,SO₄,OH)₂|(Al₆Si₆O₂₄)], with varying amounts of Calcite, Pyrite, and Sodalite.)
Quartz
Silicon Dioxide (SiO₂)
Calcite
Calcite (Calcium Carbonate, CaCO3)
Slag
Ferrous slag (by-product of iron smelting)
Gneiss (High-grade Metamorphic Rock)
Gneiss (Metamorphic silicate rock)
Calcite
Calcite (CaCO₃)
Pyrite
Iron Disulfide (FeS2)
Pyrite
Iron Sulfide (FeS2)
Biotite Mica
K(Mg,Fe)3AlSi3O10(OH)2