Placer Gold Nugget
Native Gold (Au)
Category
Browse sedimentary (processed mineral product) specimens identified by the Rock Identifier community.
Placer Gold Nugget
Native Gold (Au)
Sandstone (Banded)
Clastic Sedimentary Rock (primarily SiO2)
Serpentinite
Serpentinite (composed primarily of Serpentine group minerals: (Mg,Fe)3Si2O5(OH)4)
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2 with Iron inclusions)
Milky Quartz
Silicon Dioxide (SiO2)
Greenschist (Greenstone)
Greenschist
Yellow Calcite
Calcium Carbonate (CaCO3)
Sandstone
Arenite (primarily SiO2)
Satin Spar (often marketed as Selenite)
Fibrous Gypsum (CaSO4·2H2O)
Sandstone (Micaceous)
Arenite (composed primarily of SiO2)
Pyrite
Iron Sulfide (FeS2)
Greenstone / Serpentinite
Serpentinite (composed largely of Serpentine group minerals, Mg3Si2O5(OH)4)
Red Slag Glass
Amorphous Silica (Industrial byproduct with metallic oxide dopants)
Green Quartzite (Aventurine-like)
Quartzite (primarily SiO2 with chromium-rich mica or chlorite inclusions)
Mica Schist
Mica Schist (Complex Silicate Rock)
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Amethyst
SiO2 (Silicon Dioxide with Iron impurities)
Green Aventurine
Silicon dioxide (SiO2) with inclusions of Fuchsite mica
Limonite (Iron Ore)
Limonite (FeO(OH)·nH2O)
Magnetite
Magnetite (Fe3O4)
Quartz Geode
Silicon Dioxide (SiO2)
Halite (Rock Salt)
Halite; NaCl (Sodium Chloride)
Black Onyx
Silicon Dioxide (SiO2) with cryptocrystalline structure
Quartz Geode
Silicon Dioxide (SiO2)
Satin Spar (often sold as Selenite)
Gypsum (CaSO4·2H2O)
Bornite
Bornite (Cu5FeS4)
Quartz Pebble
Silicon Dioxide (SiO2)
Amethyst Lace Agate / Banded Amethyst
Silicon Dioxide (SiO2) with Fe3+ impurities
Diamond (or Cubic Zirconia)
Carbon (C) or Zirconium Dioxide (ZrO2)
Tiger's Eye (Rough Slab)
Pseudomorph of Quartz after Crocidolite (SiO2 with Fe-containing inclusions)
Quartz Pebble
Silicon Dioxide (SiO2)
Quartz (Iron-Stained Quartz Pebble)
Silicon Dioxide (SiO2)
Specular Hematite (Specularite)
Iron Oxide (Fe2O3)
Ironstone (likely Limonite or Goethite nodule)
Hydrothermally altered Ferric Hydroxide (FeO(OH)·nH2O)
Ironstone Concretions (Ironstone)
Ferruginous Sandstone or Siltstone (Fe2O3)
Limonite with Hematite
Limonite (FeO(OH)·nH2O) and Hematite (Fe2O3)
Sandstone
Arenite (SiO2 principal)
Engineered Quartz Stone
Agglomerated Quartz (SiO2 + Polymer Resin)
Quartz Crystal Cluster
Silicon Dioxide (SiO2)
Sandstone
Arenite
Quartz Pebble
Silicon Dioxide (SiO2)
Breciated Limestone with Calcite Veins
Sedimentary Breccia (CaCO3)