Mineral (Evaporite)

Massive Quartz

Silicon dioxide (SiO2)

Quartz Geode

Silicon Dioxide (SiO2)

Sandstone (Iron-stained)

Arenite (primarily SiO2 with Fe2O3 staining)

Sandstone (Banded)

Clastic Sedimentary Rock: Arenite

Quartz (Chatoyant or Milky variety)

Silicon Dioxide (SiO2)

Magnetite

Magnetite (Fe3O4)

Quartz Geode

Silicon Dioxide (SiO2)

Limonite (Iron Ore)

Limonite (FeO(OH)·nH2O)

Fluorite

Calcium Fluoride (CaF2)

Native Copper

Native Copper (Cu)

Turquoise in Matrix

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

Chrysocolla in Matrix

Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O (Silicate/Secondary Copper Mineral)

Vanadinite on Barite

Pb5(VO4)3Cl (Vanadinite) with BaSO4 (Barite)

Limonite (Ironstone Concretion)

Limonite (FeO(OH)·nH2O)

Limonite Concretion (Ironstone)

Limonite / Goethite (FeO(OH)·nH2O)

Limonite (Ironstone Concretion)

Limonite (Hydrous Ferric Oxides mixed with Goethite)

Lapis Lazuli

Lazurite-rich metamorphic rock (approx. (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)

Limonite (with goethite)

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

Limonite Concretion (Ironstone)

Limonite (FeO(OH)·nH2O) / Goethite

Limonite (Gozzany Iron)

Limonite (FeO(OH)·nH2O)

Bauxite

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

Limonite (Iron Ore)

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

Scoria with Calcite Infills

Vesicular Basalt with secondary Calcification (CaCO3)

Blue Moss Agate

Silicon Dioxide (SiO2) with mineral inclusions

Kyanite in Quartz

Kyanite (Al2SiO5) with Quartz (SiO2)

Smoky Quartz

Silicon dioxide (SiO2)

Herkimer Diamond

Quartz (Silicon Dioxide, SiO2)

Larimar

Blue Pectolite (NaCa2Si3O8(OH))

Quartz with inclusions (likely Tourmaline or Biotite)

Silicon Dioxide (SiO2)

Black Opal

Hydrated Silica (SiO2·nH2O)

Lapis Lazuli

Sodium aluminum silicate with sulfur (main component: Lazurite [(Na,Ca)8(AlSiO4)6(SO4,S,Cl)2])

Magnetite or Magnetic Iron Ore

Magnetite (Fe3O4)

Travertine (Tufa)

Chemical Limestone (CaCO3)

Quartz Geode with Chalcedony

Crystalline Silicon Dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Quartz / Quartzite

Silicon Dioxide (SiO2)

Fossilized Bone Fragment

Permineralized Vertebrate Fossil (Hydroxyapatite replaced by Minerals)

Limonite with Opal infusion

FeO(OH)·nH2O (Limonite) / SiO2·nH2O (Opal)

Gold in Matrix

Native Gold (Au)

Limonite (also known as Yellow Ochre or Brown Hematite)

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

Pyrite-rich Ore

Pyrite (FeS2) with secondary minerals

Pegmatite with Schorl (Black Tourmaline) and Mica

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