Ferruginous Sandstone (Ironstone)
Sandstone with Hematite/Goethite cement (SiO2 + FeO(OH))
Category
Browse industrial byproduct (anthropogenic rock) specimens identified by the Rock Identifier community.
Ferruginous Sandstone (Ironstone)
Sandstone with Hematite/Goethite cement (SiO2 + FeO(OH))
Schist
Mica Schist (contains muscovite/biotite and quartz)
Quartz (Druzy) in host rock
SiO₂ (Silicon Dioxide) as Quartz, with unspecified host rock components (likely silicates and iron oxides)
Porphyritic Basalt
Porphyritic Basalt (with Plagioclase phenocrysts)
Quartz
Quartz (SiO2 - Silicon Dioxide)
Almandine Garnet
Almandine, Fe3Al2(SiO4)3
Chert (Chert / Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Dyed Chalcedony (Agate)
Silicon Dioxide (SiO2) with artificial pigment
Glass
Amorphous Silicon Dioxide (SiO2)
Gneiss (Metamorphic Rock)
Gneiss (variable mineral formula primarily containing Quartz, Feldspar, and Mica)
Marble
Recrystallized Calcite (CaCO3)
Quartzite
Quartzite (primarily SiO2)
Anthracite Coal
Anthracite
Riverstone Quartzite (Iron-stained)
Quartzite (primarily SiO2 with Limonite/Goethite staining)
Quartzite (or Milky Quartz pebble)
Quartzite (Metamorphosed Sandstone) / Silicon Dioxide (SiO2)
Quartzite
Quartzite (SiO2)
Iron Ore (Limonite and Hematite)
Goethite/Limonite (FeO(OH)·nH2O) and Hematite (Fe2O3)
Sodalite (blue beads) and Clear Quartz (clear beads)
Sodalite: Na4Al3Si3O12Cl; Quartz: SiO2
Sapphire in a ring
Corundum (Al2O3)
Garnet Schist
Almandine-Mica Schist
Ironstone Concretion (Limonite/Goethite)
Ferruginous concretion (Fe2O3·nH2O)
Limestone (containing Fossil Mold)
Sedimentary Calcium Carbonate (CaCO3)
Quartzite (River Pebble)
Metamorphic Quartzite (SiO2)
Diamond (in jewelry setting)
Diamond (C - Pure Carbon)
Diamond
Diamond (C)
Quartzite
Quartzite
Quartzite (River Pebble)
Metamorphosed Quartz Sandstone (SiO2)
Limestone Pebble
Limestone (Calcium Carbonate, CaCO3)
Quartz (Small Fragment)
Silicon Dioxide (SiO2)
Chalcedony
Cryptocrystalline Quartz (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Milky Quartz with Iron Inclusions
Quartz (Silicon Dioxide, SiO2)
Amethyst (Raw Quartz)
Amethyst (Silicon Dioxide with Iron impurities, SiO2)
Diamond
Diamond (pure Carbon, C)
Ruby
Corundum (Al2O3 with chromium impurities)
Stilbite
Stilbite-Ca (NaCa4(Si27Al9)O72·28H2O)
Chalcedony (Common Opal variant)
Silicon dioxide (SiO2) with varying levels of hydration
Red Garnet (Pyrope or Almandine)
Garnet Group (A3B2(SiO4)3)
Rough Quartz
Silicon Dioxide (SiO2)
Iron-stained Quartz (with Limonite/Hematite)
Silicon Dioxide (SiO2) with Iron Oxide inclusions (FeO(OH) or Fe2O3)
Black Tourmaline
Schorl (Sodium Iron Aluminum Borosilicate Hydroxide), NaFe3Al6(BO3)3Si6O18(OH)4
Quartzite Pebble
Quartzite (SiO2)