Gold Flakes
Native Gold (Au)
Category
Browse sedimentary (chemically precipitated mineral) specimens identified by the Rock Identifier community.
Gold Flakes
Native Gold (Au)
Banded Iron Formation (BIF)
Banded Iron Formation (Fe2O3 + SiO2)
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
Quartz
Silicon Dioxide (SiO2)
Pyrite
Iron Sulfide (FeS2)
Banded Sandstone
Arenite (with iron oxide banding)
Banded Iron Formation (BIF) / Tiger Iron variety
Banded Iron Formation (predominantly Hematite, Magnetite, and Chert/Quartz - SiO2 + Fe2O3)
Travertine (often colloquially called Tufa)
Chemical Sedimentary Calcium Carbonate (CaCO3)
Orange Calcite
Calcium Carbonate (CaCO3)
Blue Calcite
Calcium Carbonate (CaCO3)
Chert (Brown variety / Common Jasper)
Microcrystalline Quartz (SiO2)
Carnelian
Silicon Dioxide (SiO2) - variety of Chalcedony
Agate
Chalcedony (SiO2)
Desert Rose (Gypsum Variety)
Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Orange Calcite (often commercially sold as Honey Calcite or Aragonite)
Calcium Carbonate (CaCO3)
Chert (Nodule)
Silicon Dioxide (SiO2)
Chert (Jasper nodule)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Chert (Iron-rich)
Silicon Dioxide (SiO2) with Hematite (Fe2O3)
Gold Nugget
Native Gold (Au)
Optical Calcite
Calcium Carbonate (CaCO3)
Quartz Pebble
Silicon Dioxide (SiO2)
Azurite and Malachite
Azurite (Cu3(CO3)2(OH)2) and Malachite (Cu2(CO3)(OH)2)
Chert (often called Flint)
Chert (Microcrystalline Silicon Dioxide, SiO2)
Bauxite
Alumina-rich rock (consisting of Gibbsite, Boehmite, and Diaspore)
Concrete Paver (Artificial Cementitious Rock)
Hydrated Portland Cement Aggregate
Agate and Amethyst (Quartz variants)
Silicon Dioxide (SiO2) - Microcrystalline Quartz and Crystalline Quartz
Celestite Geode
Celestine (Strontium Sulfate, SrSO4)
Blue Calcite
Calcium Carbonate (CaCO3)
Limonite (Yellow Ochre)
Hydrated iron(III) oxide-hydroxide (FeO(OH)·nH2O)
Quartzite / Sandstone / Chert Mix
Silicon Dioxide (SiO2)
Limestone
Calcium Carbonate (CaCO3)
Chert (Yellow/Tan Variety)
Chert (SiO2)
Orange Calcite
Calcium Carbonate (CaCO3)
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
Blue Caribbean Calite
Calcium Carbonate (CaCO3) with trace Aragonite
Shale with Vein Infillings
Shale (a fine-grained clastic sedimentary rock). The veins could be Calcite (CaCO3), Quartz (SiO2), or other minerals.
Hematite Nodule
Hematite (Fe2O3)
Honey Calcite
Calcium Carbonate (CaCO3)
Bauxite
Bauxite (mainly Al(OH)3, AlO(OH))
Sandstone (Picture Sandstone)
Sandstone (primarily Quartz with Iron Oxide impurities)
Quartz Pebble
Silicon Dioxide (SiO2)