Magnetite
Magnetite (Fe3O4)
Category
Browse sedimentary (secondary mineral formation) specimens identified by the Rock Identifier community.
Magnetite
Magnetite (Fe3O4)
Selenite
Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O
Peridot
Olivine (Mg,Fe)2SiO4
Tiger's Eye (commonly referred to as Blue/Gold Tiger's Eye)
Tiger's Eye is a variety of Chalcedony (cryptocrystalline quartz), SiO2, exhibiting chatoyancy. The blue variety is often called Hawk's Eye.
Ironstone Concretion (Limonite/Goethite)
Ferruginous Sandstone or Limonite (FeO(OH)·nH2O)
Agate (Slab)
Agate (Cryptocrystalline variety of Quartz, SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Citrine Quartz
Silicon Dioxide (SiO2)
Sandstone (likely Siltstone)
Arenite or Siltstone (high SiO2 content)
Pyrite
Iron Sulfide (FeS2)
Magnetite Sand (Black Sand)
Magnetite (Fe3O4)
Ocean Jasper
Orbicular Jasper (Silicon Dioxide, SiO2)
Ferruginous Quartzite (Iron-stained Quartzite)
Quartzite with Iron oxides (FeO(OH) / Fe2O3)
Orange Quartzite (or Iron-Stained Quartz)
Silicon Dioxide (SiO2) with Iron Oxide impurities (Fe2O3)
Amazonite
K(AlSi3O8) - Microcline variant
Sandstone (Ferruginous)
Arenite (Fe-rich)
Red Jasper
Silicon Dioxide with Hematite impurities (SiO2 + Fe2O3)
Sandstone (with Iron Staining)
Clastic sedimentary rock (SiO2 with Fe2O3 oxides)
Sandstone (Calcareous or Ferruginous)
Clastic sedimentary rock (SiO2 with CaCO3 or Fe2O3 cement)
White Calcite
Calcium Carbonate (CaCO3)
Limonite Concretion (Ironstone)
Limonite (Hydrated Iron(III) Oxide-Hydroxide, FeO(OH)·nH2O)
Schist
Mica Schist
Pyrite in Matrix (Fool's Gold)
Iron Sulfide (FeS2)
Amethyst
Silicon Dioxide (SiO2) with iron impurities
White Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Milky Quartz (Tumbled)
Quartz (Silicon Dioxide, SiO2)
Carnelian Agate
Silicon Dioxide (SiO2) - Variety: Chalcedony
Amethyst
Silicon dioxide (SiO2)
Sandstone (Ferruginous)
Arenite with Iron-Oxide Cement (primarily SiO2 with Fe2O3/FeOOH)
Banded Onyx (Mexican Onyx / Travertine)
Calcite (CaCO3) - Banded Travertine
Concrete with Aggregate
Artificial Conglomerate (Cement and Aggregate)
Yellow Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
Sandstone
Arenite (composed primarily of SiO2)
Sandstone
Arenite (Siliclastic Sedimentary Rock)
White Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Gneiss
Gneiss (High-grade metamorphic rock)
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Fe2O3 cement)
Sandstone (Quartzose)
Arenite (composed primarily of SiO2)
Blue Apatite
Fluorapatite (Ca5(PO4)3F)