Mineral, Metal (Element)

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

Opalite (Man-made Glass)

Synthetic Opalised Glass

Fossil bone or tooth fragment

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

Pyrite

Iron Sulfide (FeS2)

Likely weathered metallic mineral or slag fragment

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

Gold Ore in Quartz

Auriferous Quartz (Au + SiO2)

Pink faceted gemstone, likely amethyst or pink quartz

Quartz (SiO₂), likely pale amethyst; exact identification requires testing

Quartz Vein in Host Rock (Gabbro or Basalt)

Silicon Dioxide (SiO2) with Mafic Silicates

Granite

Felsic intrusive igneous rock

Native Copper

Native Copper (Cu)

Pink Granite

Granite (Phaneritic Quartz-Feldspar rock)

Indeterminate metallic mineral fragments

Possibly pyrite, chalcopyrite, or metallic sulfide-bearing rock

Costume Jewelry with Synthetic Gemstones

Synthetic Cubic Zirconia and Glass (SiO2 / ZrO2)

Limonite and Goethite on Gossan

FeO(OH)·nH2O

Limonite and Goethite encrusted Quartz (Iron-stained Gossan)

FeO(OH)·nH2O (Limonite) / FeO(OH) (Goethite) on SiO2 (Quartz)

Blue glass-like bead or gemstone keychain ornament

Indeterminate; likely cobalt-blue glass or synthetic blue spinel, not identifiable as a natural mineral from the image

Opalite

Synthetic Opalite Glass / Opalized Glass

Pyrite

Iron Disulfide (FeS2)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Polished smoky quartz or brown chalcedony pebble

Silicon dioxide (SiO₂), likely quartz/chalcedony with iron-oxide inclusions

Gossan (Iron Hat) with Quartz and Chlorite

Limonite/Goethite-rich Gossan (FeO(OH)·nH2O) with inclusions of Quartz and Chlorite

Pyrite (on a metal substrate)

Iron Sulfide (FeS2)

Quartz (Clear or Milky)

Silicon Dioxide (SiO2)

Quartz Vein in Host Rock

Crystalline Silicon Dioxide (SiO2) in Igneous/Metamorphic Matrix

Quartz Vein in Sedimentary Matrix

Silicon Dioxide (SiO2) with host rock

Quartz Vein in Host Rock

Silicon Dioxide (SiO2) in matrix

Green Slag Glass

Amorphous Silica Glass (Anthropogenic)

Green aventurine beads

Aventurine quartz, SiO₂, colored green by fuchsite or other inclusions

Cubic Zirconia (Diamond Simulant)

Zirconium Dioxide (ZrO2)

Emerald and Diamond (Jewelry Setting)

Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities) and Carbon (C)

Quartz Vein in Host Rock (Gossanous Matrtix)

Silicon Dioxide (SiO2) with iron oxides (Limonite/Hematite)

Diamond (set in jewelry)

Diamond (Carbon, C)

Diamond (in a gold ring)

Diamond (pure carbon, C)

Polished native copper

Native copper (Cu), likely with cuprite/tenorite oxidation products

Turquoise inlay ring

Turquoise, CuAl₆(PO₄)₄(OH)₈·4H₂O

Granite

Intrusive igneous rock

Limonite (Gossan)

FeO(OH)·nH2O (Hydrated Iron Oxide)

Turquoise cabochon ring

Turquoise — hydrated copper aluminum phosphate, CuAl₆(PO₄)₄(OH)₈·4H₂O

Amethyst and clear gemstone ring

Amethyst (purple quartz, SiO₂), likely set with colorless quartz or glass accents

Serpentinite

Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)2-3(Si, Al, Fe)2O5(OH)4