Hematite
Iron(III) oxide (Fe2O3)
Category
Browse mineral (sedimentary context) specimens identified by the Rock Identifier community.
Hematite
Iron(III) oxide (Fe2O3)
Hematite
Iron (III) Oxide, Fe2O3
Quartz (Milky/Vein Quartz)
Silicon Dioxide (SiO2)
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
Quartz Geode
Silicon Dioxide (SiO2)
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Hematite
Iron(III) oxide (Fe2O3)
Banded Agate
Chalcedony (Silicon Dioxide, SiO2)
Yellow Calcite
Calcite (Calcium Carbonate, CaCO3)
Chert (often called Flint when dark or found in chalk)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Jasper (Yellow Jasper)
Silicon Dioxide (SiO2) with iron inclusions
Clear Quartz Crystal
Silicon Dioxide (SiO2)
Bauxite
Bauxite (Al(OH)3 mixed with Fe2O3 and clay minerals)
Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Garnet (Almandine)
Almandine Garnet (Fe3Al2(SiO4)3)
Fluorite
Calcium Fluoride (CaF2)
Sand Grain (Silica/Quartz Grain)
Silicon Dioxide (SiO2)
Yellow Jasper
Jasper (Silicon Dioxide, SiO2)
Jasper
Jasper / Silicon Dioxide (SiO₂)
Jasper (with Manganese or Iron inclusions)
Silicon Dioxide (SiO2)
Quartz Veinated Sandstone or Siltstone
Silicon Dioxide (SiO2) within a clastic sedimentary matrix
Sandstone
Arenite (composed primarily of SiO2)
Ferruginous Sandstone (Ironstone Nodules)
Ferruginous Sandstone with Limonite/Goethite coating (Fe2O3·H2O)
Red Sandstone
Arenite (predominantly Quartz with Hematite cementation)
Red Sandstone
Arenite
Sandstone
Clastic sedimentary rock (primarily SiO2)
Sandstone (likely Graywacke or Arkosic varieties)
Arenite (composed primarily of SiO2)
Sandstone (with possibly iron oxides and other minerals)
Sandstone
Limonite Pseudomorph after Pyrite
Goethite/Limonite FeO(OH)·nH2O replacing Pyrite FeS2
Sandstone (Quartzite-rich)
Clastic Sedimentary Rock (primarily SiO2)
Sandstone (likely Quartzose Sandstone)
Arenite (primarily SiO2)
Sandstone
Clastic sedimentary rock (primarily SiO2)
Quartz (likely Herkimer Diamond style)
Silicon Dioxide (SiO2)
Sandstone
Arenite (composed primarily of SiO2)
Banded Sandstone
Arenite (with iron oxide banding)
Sandstone (Ferruginous)
Arenite (composed primarily of SiO2 with Fe2O3 staining)
Green Sandstone
Glauconitic Sandstone
Sandstone
Arenite (primarily SiO2)
Agatized Fossil (Druzy Agate)
Silicon Dioxide (SiO2) replacing organic matter
Shungite
Non-crystalline carbon (allotrope of carbon)
Quartz (likely Jasper or Chert variety)
Quartz (SiO₂)
Jasper (Red Jasper)
Silicon Dioxide (SiO2) with iron oxide inclusions