Metal (Elemental Mineral)

Milky Quartz

Silicon Dioxide (SiO2)

Quartz Vein in Matrix (Gneiss/Schist)

Silicon Dioxide (SiO2) in Metamorphic Rock Matrix

Lepidolite in Mica Schist

K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2

Serpentinite

Serpentinite (Mg, Fe, Ni)3Si2O5(OH)4

Quartz Vein in Host Rock

Silicon Dioxide (SiO2)

Native Copper

Native Copper (Cu)

Milky Quartz

Silicon Dioxide (SiO2)

Granite Pebble with Quartz Vein

Granite (Plutonic Igneous Rock) with Quartz (SiO2)

Quartz vein in metamorphic rock

Crystalline Silicon Dioxide (SiO2) in Host Rock

Native Copper (Penny specimen)

Native Copper (Cu)

Limonite and Goethite

Limonite (hydrated iron(III) oxide-hydroxide) and Goethite (α-FeO(OH))

Bismuth

Bismuth (Bi)

Sandstone (Whetstone/Sharpening Stone)

Siliciclastic Sandstone (SiO2 dominant)

Gold-Bearing Quartz Ore

Crystalline Silicon Dioxide (SiO2) with Trace Aurum (Au)

Gold Nugget / Flake

Native Gold (Au)

Rose Quartz and Lepidolite in Pegmatite

Crystalline Silicon Dioxide (SiO2) with Lithium-rich Mica (K(Li,Al)3(Al,Si)4O10(F,OH)2)

Granite

Felsic intrusive igneous rock

Chromite

Chromite (FeCr2O4)

Beryl (Aquamarine)

Be3Al2Si6O18

Quartz-rich metallic sulfide ore (probable pyrite-bearing rock)

Pyrite, FeS₂, in a quartz-rich host; exact identification is uncertain from the image

Green Schist

Greenschist (Chlorite Schist)

Amethyst (in jewelry)

Silicon Dioxide (SiO2) with iron impurities

Sandstone (Ferruginous)

Arenite with Iron-Oxide Cement (primarily SiO2 with Fe2O3/FeOOH)

Native Copper Nugget

Native Copper (Cu)

Quartz (River Pebble)

Silicon Dioxide (SiO2)

Bauxite

Bauxite (mixture including Gibbsite Al(OH)3, Boehmite γ-AlO(OH), and Diaspore α-AlO(OH))

Milky Quartz

Silicon Dioxide (SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Gossan (Iron Hat)

Hydrous Iron Oxides (predominantly Goethite FeO(OH) and Limonite)

Amygdaloidal Basalt

Basalt with secondary mineral infilling

Granite

Intrusive Igneous Rock

Banded Calcite (Mexican Onyx)

Calcium Carbonate (CaCO3)

Beryl (Aquamarine)

Beryllium Aluminum Cyclosilicate (Be3Al2Si6O18)

Milky Quartz

Silicon Dioxide (SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Vanadinite

Vanadinite (Pb5(VO4)3Cl)

Gossan (Iron Cap)

Limonitic Gossan (Fe2O3·nH2O mixed)

Biotite-rich mica schist

Mica schist, dominated by biotite mica (K(Mg,Fe)₃AlSi₃O₁₀(F,OH)₂), with probable quartz and feldspar

Gold Ore

Gold-bearing Quartz (Native Gold, Au)

Granite

Intrusive Igneous Rock

Moss Agate

Chalcedony (SiO2) with inclusions of manganese or iron oxides

Moss Agate

Silicon dioxide (SiO2) with inclusions