Diamond
Carbon (C)
Category
Browse synthetic or natural fiber specimens identified by the Rock Identifier community.
Diamond
Carbon (C)
Limonite and Goethite on Gossan
FeO(OH)·nH2O
Smoky Quartz
Smoky Quartz (SiO2 - Silicon Dioxide with trace impurities of aluminum)
Celestine (Celestite)
Strontium sulfate (SrSO4)
Pearl
Biogenic CaCO3 (Aragonite and Calcite)
Conglomerate
Conglomerate
Conglomerate
Clastic sedimentary rock (Conglomerate)
Orange Quartz (Citrine or Iron-stained Quartz)
Silicon Dioxide (SiO2)
Silver (Morgan Dollar)
Native Silver (Ag) - 90% Silver, 10% Copper alloy
Hag Stone (Banded Chert or Limestone with Borehole)
Microcrystalline Quartz (Chert) or Calciferous Siltstone (CaCO3/SiO2)
Iron Ore (Magnetite-Hematite)
Magnetite (Fe3O4) and Hematite (Fe2O3)
Diamond (Cut jewelry specimen)
Diamond (pure Carbon, C)
Diamond
Diamond (pure carbon C)
Granite
Granite (phaneritic intrusive igneous rock consisting of quartz, feldspar, and mica)
Basalt (River Pebble)
Extrusive Mafic Igneous Rock
Moonstone (Tumbled)
Orthoclase Feldspar (KAlSi3O8) with inclusions of Albite
Diamond (as featured in jewelry)
Diamond (C - pure carbon)
Granite
Granite (Felsic Plutonic Rock)
Diamond
Diamond (C)
Magnetite / Ironstone
Magnetite (Fe3O4)
Sandstone (River Cobble)
Sandstone (primarily composed of silica, SiO2)
Amethyst (Faceted)
Quartz (SiO2) with iron impurities
Amethyst (Agate/Chalcedony variety)
Silicon Dioxide (SiO2) with iron impurities
Jasper Pebble
Silicon dioxide (SiO2) with iron oxide impurities
Tektite (specifically Indochinite)
Tektite (Natural silica glass)
Cullet (Slag Glass)
Amorphous Silica (Industrial byproduct)
Dyed Blue Quartzite
SiO2 (Silicon Dioxide) with artificial colorants
Heat-Treated Citrine (Amethyst)
Silicon Dioxide (SiO2) with iron impurities
Tektite (Indochinite)
Tektite (Natural silica glass)
Sandstone
Arenite (SiO2 based)
Coquina
Bioclastic Limestone
Mixed Mineral Collection (with Titanium Aura Quartz)
Silicon Dioxide (SiO2) with metallic coatings and various silicates
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Banded Agate (Dyed Purple)
Agate (Variety of Chalcedony/Quartz), SiO2
Blue Dyed Agate
Silicon Dioxide (SiO2)
Diamond
Diamond (Native Carbon, C)
Dyed Howlite (Purple)
Calcium Borosilicate Hydroxide (Ca2B5SiO9(OH)5)
Quartz (Gray or Smoky variety)
Silicon Dioxide (SiO2)
Aventurine
Silicon Dioxide (SiO2 with inclusions of Fuchsite mica)
Peacock Ore (Bornite or Chalcopyrite)
Bornite (Cu5FeS4) or Acid-Washed Chalcopyrite (CuFeS2)
Citrine
Silicon Dioxide (SiO2)
Yellow Calcite
Calcium Carbonate (CaCO3)