Mineral (Processed Metal)

Titanium Aura Quartz

Titanium-coated Silicon Dioxide (SiO2)

Green aventurine pendant (likely)

Quartz, SiO₂, with green fuchsite inclusions (aventurescent quartz)

Granite

Granite (Felsic Plutonic Rock)

Lapis lazuli bead bracelet

Lapis lazuli, chiefly lazurite (Na₃Ca(Si₃Al₃)O₁₂S); commonly with calcite and pyrite

Gossan (Limonite/Ironstone)

Hydrated Iron Oxide (FeO(OH)·nH2O)

Sandstone (Quartzose)

Arenite (predominantly SiO2)

Weathered gold-bearing quartz vein fragment

Quartz (SiO₂) with probable iron oxides and sulfide/mineral inclusions

Quartzite

Quartzite (primarily SiO2)

Granite

Phaneritic Felsic Igneous Rock

Native Copper

Copper (Cu)

Quartz-rich pegmatite with mica

Granitic pegmatite; chiefly quartz (SiO₂), feldspar, and muscovite/biotite mica

Quartz Vein in Siltstone

SiO2 (Quartz) on clastic sedimentary matrix

Quartzite (Yellow/Iron-Stained)

Quartzite (SiO2 with Iron Oxide impurities)

Native gold-bearing quartz vein specimen

Native gold (Au) in quartz, with possible iron-oxide and sulfide minerals

Iron-stained quartz-bearing rock (probable weathered quartz vein or ironstone)

Quartz (SiO₂) with goethite/limonite iron oxides; possibly altered volcanic or metamorphic host rock

Black-and-white agate geode pendant

Agate (microcrystalline quartz, SiO₂), likely a hollow geode slice with chalcedony and drusy quartz

Quartz Vein in Host Rock

Silicon Dioxide (SiO2) within metamorphic/igneous matrix

Granite

Intrusive Igneous Rock

Granite

Granite (felsic intrusive igneous rock)

Quartz vein in Host Rock

Crystalline Silicon Dioxide (SiO2) in Lithic Matrix

Pallasite Meteorite (Sliced and Polished)

Pallasite (Iron-Nickel Matrix with Olivine crystals)

Peacock Ore (Chalcopyrite)

Chalcopyrite (CuFeS2)

Gold-bearing quartz or iron-stained quartzite

Quartz (SiO₂), possibly with native gold and iron oxides

Fossil bone or tooth fragment

Mineralized fossil vertebrate bone/tooth; exact taxon cannot be determined from the photograph

Rhodochrosite (Beads) and Citrine (Pendant)

Rhodochrosite (MnCO3) and Quartz variety Citrine (SiO2)

Quartz-veined Metamorphic Rock

Quartz Vein in Phyllite or Schist (SiO2 in Silicate Matrix)

Granite

Intrusive igneous rock

Bismuth crystal

Bismuth (Bi), commonly laboratory-grown hopper crystal

Gold Nugget

Native Gold (Au)

Polished banded agate, likely moss or dendritic agate

Microcrystalline quartz (chalcedony), SiO₂, with iron/manganese inclusions

Gold Nugget

Native Gold (Au)

Likely weathered metallic mineral or slag fragment

Indeterminate; possibly iron-rich sulfide/oxide material or industrial slag

Orange Calcite with Siderite/Iron Oxide Coating

Calcium Carbonate (CaCO3)

Quartzite (or Milky Quartz pebble)

Quartzite (primarily Silicon Dioxide, SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Zircon

Zircon (Zirconium Silicate - ZrSiO4)

Lepidolite

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

Quartz Pebble

Silicon Dioxide (SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Lepidolite

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

Goethite / Limonite Gossan

Hydrated Iron Oxide (FeO(OH))

Pyrite

Iron Sulfide (FeS2)