Gneiss
Gneiss
Category
Browse sedimentary (secondary classification for a weathered mineral specimen) specimens identified by the Rock Identifier community.
Gneiss
Gneiss
Amygdaloidal Basalt
Amygdaloidal Basalt (extrusive volcanic rock)
Chert Pebble/Nodule
Chert (a microcrystalline or cryptocrystalline sedimentary form of quartz, SiO2)
Chert (often called Flint or River Pebble)
Microcrystalline Quartz (SiO2)
Banded Jasper with Hematite or Quartz
Silicon Dioxide (SiO2) with impurities
Chert (Jasper/Chalcedony variety)
Microcrystalline Quartz (SiO2)
Jasper with Quartz Druzy
Silicon Dioxide (SiO2)
Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
Vesicular Basalt with Quartz
Vesicular Basalt (SiO2 inclusions)
Agate (Dyed High-Grade Polished Slice)
Silicon dioxide (SiO2), Chalcedony crystal variety
Basalt
Basalt (Aphanitic Mafic Volcanic Rock)
River Pebble (Greywacke or Basaltic)
Massive Greywacke or Basaltic Andesite
Slate
Foliated Metamorphic Rock (Mainly composed of Quartz, Illite, Chlorite)
Gold Nugget
Native Gold (Au)
Quartz (Beach Pebble)
Silicon Dioxide (SiO2)
Basalt with Iron Oxidation
Mafic Igneous Rock (primarily Plagioclase and Pyroxene)
Quartzite
Quartzite (primarily SiO2)
Serpentinite
Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)2-3(Si, Al, Fe)2O5(OH)4
Milky Quartz
Crystalline Silicon Dioxide (SiO2)
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Quartz (Milky Quartz pebble)
Silicon Dioxide (SiO2)
Quartz / Quartzite
Silicon Dioxide (SiO2)
Quartz with Iron Staining
Silicon Dioxide (SiO2)
Petrified Wood
Silicified wood (Quartz variant, SiO2)
Chert (Jasper and Chalcedony)
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (primarily SiO₂ - Silicon Dioxide)
Chert (Cherty Limestone or Flint)
Microcrystalline Silica (SiO2)
Chert (Jasper)
Microcrystalline Quartz (SiO2)
Blue Sapphire (faceted in jewelry)
Corundum (Al2O3)
Chert (Jasper variety)
Silicon Dioxide (SiO2)
Jasper
Silicon dioxide (SiO2)
Corundum
Corundum (Al2O3)
Rough Sapphire (Corundum)
Corundum (Al2O3)
Diamond
Carbon (C)
Pallasite Meteorite
Pallasite (Stony-iron meteorite; Fe-Ni alloy with (Mg,Fe)2SiO4 olivine)
Bauxite Ore
Hydrated aluminum oxides (e.g., Gibbsite Al(OH)3, Boehmite ̲̲̲̲AlOOH, Diaspore ̲̲̲̲AlOOH)
Green Aventurine
Quartzite with Fuchsite inclusions (SiO2 + K(Al,Cr)2(AlSi3O10)(OH)2)
Chert (and Flint)
Silicon Dioxide (SiO2)
Black Marble
Recrystallized Carbonate Rock (CaCO3)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Pyrite
Iron Sulfide (FeS2)
Rhodonite
Rhodonite (MnSiO3)