Amethyst
Amethyst (Silicon Dioxide, SiO2 + Fe4+ impurities)
Category
Browse antropogenic (man made material) specimens identified by the Rock Identifier community.
Amethyst
Amethyst (Silicon Dioxide, SiO2 + Fe4+ impurities)
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
Pyrite
Iron Sulfide (FeS2)
Angel Aura Quartz (Treated Clear Quartz)
Silicon Dioxide (SiO2) coated with Vaporized Silver and Platinum
Chert (variations include Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Blue Sphalerite (likely dyed or treated Druzy Quartz/Agate)
Zinc Sulfide (ZnS) or Silicon Dioxide (SiO2) with trade-name enhancement
Specular Hematite (Specularite)
Iron Oxide (Fe2O3)
Granodiorite with Quartz Veining
Granodiorite (containing Plagioclase Feldspar, Quartz, and Biotite/Hornblende) with Quartz (SiO2) veins
Green Slag Glass
Amorphous Silica / Glassy Blast Furnace Slag
Orbicular Granite (specifically Mustard or Yellow Tonalite/Granodiorite)
Orbicular Quartz Diorite / Tonalite
Obsidian
Volcanic Glass (Amorphous SiO2)
Moonstone
Orthoclase Feldspar (formula: (K,Na)AlSi3O8)
Chert (Jasper variety)
Silicon Dioxide (SiO2)
Grey Granite
Phaneritic Felsic Intrusive Igneous Rock
Pearl (Biogenic)
Nacre / Calcium Carbonate (CaCO3)
Sunstone
Aventurine Feldspar (Plagioclase Feldspar with inclusions)
Basaltic Tuff / Volcanic Breccia
Pyroclastic Breccia / Lithic Tuff
Pearl (with Peridot)
Calcium carbonate (CaCO3) + Conchiolin; Peridot: Magnesium iron silicate (Mg, Fe)2SiO4
Chert (Iron-stained)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Chert Pebble
Microcrystalline silica (SiO2)
Chert (specifically Red Chert or Jasper)
Microcrystalline Quartz (SiO2)
Chert (Jasper variety)
Silicon Dioxide (SiO2)
Diamond
Diamond (pure Carbon, C)
Granite
Phaneritic Plutonic Felsic Rock
Sandstone
Arenite (primarily SiO2)
Coquina or Fossiliferous Limestone
Fossiliferous Calcarenite (CaCO3)
Blue-dyed Quartz Druzy
Silicon Dioxide (SiO2) with artificial pigment
Lapis Lazuli
A metamorphic rock primarily composed of lazurite (Na,Ca)8[(S,SO4,Cl)2|(Al6Si6O24)], calcite (CaCO3), and pyrite (FeS2).
Banded Calcite (often sold as Mexican Onyx or Aragonite)
Calcite/Aragonite (Calcium Carbonate, CaCO3)
Rhyolitic Tuff
Rhyolitic Tuff / Pyroclastic rock
Diamond (or Diamond Simulant)
Carbon (C)
Granite
Granite
Chert (Field-collected Arrowhead-shaped Fragment)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Native Silver
Silver (Ag)
Fossiliferous Limestone (Coquina)
Biogenic Limestone (Calcium Carbonate, CaCO3)
Chert (specifically Gray/Blue-Gray Chert)
Chert (SiO2)
Chert (or possibly Flint)
Chert (variant: Flint)
Petrified Wood (Jet or Coalified Wood appearance)
Silicified wood (principally SiO2) or Carbonized Wood
Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, formula SiO2)
Pyrite
Iron Disulfide (FeS2)
Asphalt (Bituminous Concrete)
Asphaltum / Bitumen-Aggregate Matrix
Asphalt (Bituminous Concrete)
Bituminous mix / Anthropogenic conglomerate