Mineral (Native Element Alloy)

Biotite Schist (likely)

Biotite Schist (rock), Biotite (mineral)

Pyrite-rich Ore

Pyrite (FeS2) with secondary minerals

Banded Agate (Jasper-Agate)

Silicon Dioxide (SiO2) - Chalcedony Variety

Tiger's Eye

Tiger's eye (Pseudomorph of Quartz after Crocidolite), SiO2

Sandstone (likely River-tumbled Picture Sandstone)

Arenite (predominantly SiO2 with iron oxide impurities)

Pyrite

Iron Sulfide (FeS2)

Hematite (Iron Ore)

Hematite (Fe2O3)

Green Calcite

Calcium Carbonate (CaCO3)

Malachite

Copper carbonate hydroxide, Cu2CO3(OH)2

Aquamarine (Rough)

Beryl (Be3Al2Si6O18)

Amethyst

Amethyst (Silicon Dioxide SiO2 + Fe4+)

Amethyst

Silicon Dioxide (SiO2) with traces of Iron (Fe3+)

Calcite on Limestone

Calcium Carbonate (CaCO3) on Sedimentary Rock

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Granitic Gneiss

Gneiss (high-grade metamorphic rock)

Satin Spar (often sold as Selenite)

Gypsum (Calcium Sulfate Dihydrate, CaSO4·2H2O)

Lapis Lazuli

Lazurite-rich metamorphic rock

Malachite or Chrysocolla on Host Rock

Cu2(CO3)(OH)2 (Malachite) or (Cu,Al)2H2Si2O5(OH)4 (Chrysocolla)

Hematite (beads)

Hematite (Fe₂O₃)

Turquoise

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

Rhodonite

(Mn,Fe,Mg,Ca)SiO3

Sandstone (with Limonite/Iron Staining)

Arenite (SiO2 based) with FeO(OH) staining

Sandstone (Iron-stained)

Arenite with Limonite/Hematite staining

Limonite (Ironstone Concretion)

Limonite (FeO(OH)·nH2O)

Sandstone

Sandstone (clastic sedimentary rock)

Concretion with Geode Cavity

Ferruginous Sandstone Concretion with Quartz Center

Milky Quartz with Iron Staining

Quartz (Silicon Dioxide, SiO2)

Turquoise (possible Dyed Howlite or Magnesite imitation)

CuAl6(PO4)4(OH)8·4H2O (Turquoise)

Ferruginous Quartz (Iron-Stained Quartz)

Silicon Dioxide (SiO2) with Iron Oxide inclusions

Red Sandstone (Iron-Rich)

Arenite (Fe2O3)

Turquoise

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

Azurite with Malachite and Limonite

Azurite Cu3(CO3)2(OH)2 / Malachite Cu2CO3(OH)2

Red Sandstone

Arenite (Ferruginous Sandstone)

Red Sandstone (with possible iron oxide staining)

Sandstone (primarily Quartz with Hematite/Goethite cement)

Turquoise

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

Turquoise

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

Limonite

Limonite (Hydrous iron oxides, FeO(OH)·nH2O)

Turquoise

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

Quartz Vein in Host Rock (Gneiss/Schist)

Silicon Dioxide (SiO2) within a metamorphic matrix

Red Sandstone

Arenite (with Iron Oxide cement)

Sandstone with Iron Oxide (Limonite/Hematite)

Ferruginous Sandstone (SiO2 with FeO(OH)·nH2O)

Moonstone

Orthoclase (Potassium Feldspar) - (K,Na)AlSi3O8