Mineral (Extraterrestrial)

Limonite Concretion (Ironstone)

Limonite (FeO(OH)·nH2O) / Goethite

Limonite (with goethite)

Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)

Bauxite

Bauxite (Al(OH)3, γ-AlO(OH), and α-AlO(OH))

Limonite (Gozzany Iron)

Limonite (FeO(OH)·nH2O)

Limonite (Iron Ore)

Limonite (Hydrous ferric oxides), generic formula FeO(OH)·nH2O

Biotite Schist (likely)

Biotite Schist (rock), Biotite (mineral)

Banded Gneiss (with possible weathered sulfide or iron staining)

Gneiss, potentially with iron oxide/hydroxide staining (e.g., limonite) or weathered sulfides

Pegmatite with Schorl (Black Tourmaline) and Mica

Pegmatite (complex association of NaAlSi3O8, NaFe3Al6(BO3)3Si6O18(OH)4, and KAl2(AlSi3O10)(OH,F)2)

Quartz / Quartzite

Silicon Dioxide (SiO2)

Kyanite in Quartz

Kyanite (Al2SiO5) with Quartz (SiO2)

Heat-Treated Amethyst (Commercial Citrine)

Silicon Dioxide (SiO2) - Macro-crystalline Quartz

Banded Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

Gneiss (specifically a Granitic Gneiss specimen)

Gneiss (high-grade metamorphic rock primarily composed of Quartz, Feldspar, and Biotite/Amphibole)

Limestone with Secondary Mineralization

Calcium Carbonate (CaCO3)

Gemstone Sand (Mineral Assortment)

Mixed Mineral Concentrates (Commonly including Quartz SiO2, Garnet X3Y2(SiO4)3, and Tourmaline (Na,Ca)(Li,Mg,Al)3(Al,Fe,Mn)6(BO3)3(Si6O18)(OH,F)4)

Milky Quartz with Mineral Inclusions

Silicon Dioxide (SiO2) with miscellaneous inclusions

Milky Quartz with Mineral Inclusions

Quartz (Silicon Dioxide, SiO2)

Limonite with Hematite

Hydrated iron(III) oxide-hydroxide with variable composition (FeO(OH)·nH2O)

Malachite

Cu2CO3(OH)2 (Copper Hydroxide Carbonate)

Sandstone with Iron Banding

Arenite with Hematite or Limonite staining (SiO2 with Fe2O3)

Turquoise (likely stabilized or simulated Howlite)

CuAl6(PO4)4(OH)8·4H2O (Hydrous phosphate of copper and aluminium)

Yellow Aventurine

Quartz (Silicon Dioxide) with Mica inclusions (SiO2)

White Calcite

Calcium Carbonate (CaCO3)

Limonite with Trace Fossils

Hydrous Iron Oxide Mixture (FeO(OH)·nH2O)

Limonite (Ironstone)

Limonite (Hydrated iron(III) oxide-hydroxide, FeO(OH)·nH2O)

Chrysocolla in Malachite

Cu2CO3(OH)2 (Malachite) / Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O (Chrysocolla)

Turquoise in Matrix

Hydrated phosphate of copper and aluminium: CuAl6(PO4)4(OH)8·4H2O

Limonite Concretion

Limonite (Hydrated Iron Oxide) FeO(OH)·nH2O

Vesicular Basalt with Secondary Mineral Infill

Mafic Volcanic Rock (Basalt)

Gold in Matrix

Native Gold (Au)

Rutilated Quartz

Silicon Dioxide (SiO2) with inclusions of Titanium Dioxide (TiO2)

Limonite (Iron-rich Siltstone / Sandstone base)

Hydrous ferric oxide mixture (FeO(OH)·nH2O)

Gneiss (specifically a Banded Gneiss pebble)

Gneiss (High-grade Regional Metamorphic Rock)

Pyrite

Iron Sulfide (FeS2)

Granite (Thin Section)

Granite (Felsic Plutonic Rock)

Quartz with Pyrite inclusions

Silicon Dioxide (SiO2) with Iron Sulfide (FeS2)

Sandstone (with potential iron mineralization)

Arenite

Copper Ore (likely Chalcopyrite in Matrix)

Chalcopyrite (CuFeS2)

Sandstone (Tumbled/River Pebble)

Arenite (composed primarily of SiO2)

Native Copper

Native Copper (Cu)

Hematite (Concretion)

Iron(III) oxide (Fe2O3)

Quartz (Granular Milky Quartz fragment)

Silicon Dioxide (SiO2)