Mineral (Processed Metal)

Iron-stained quartz vein in weathered host rock

Quartz (SiO₂) with iron-oxide/hydroxide staining; host rock undetermined

Pearl (Imitation or Cultured)

Calcium Carbonate (Aragonite/Calcite) - CaCO3

Iron-stained Quartz (Gossan/Limonite-coated Quartz)

Silicon Dioxide (SiO2) with Hydrated Iron Oxides (FeO(OH)·nH2O)

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Granite

Felsic intrusive igneous rock

Amethyst (in jewelry)

Silicon Dioxide (SiO2) with iron impurities

Man-made Slag (Industrial Byproduct)

Anthropogenic Glassy Residue

Bismuth

Bismuth (Bi)

Quartz Vein Rock

Quartz (Silicon Dioxide, SiO2)

Ferruginous Sandstone

Sandstone with Iron Oxide (Limonite/Goethite)

Dyed Howlite (simulating Lavender/Purple Jade or Charoite)

Howlite: Ca2B5SiO9(OH)5 (when natural)

Shale with Plant Fossils / Carbonaceous Shale

Laminated Mudrock (Siliciclastic)

Pyrite

Iron Sulfide (FeS2)

Quartzite Pebble

Quartzite (primarily SiO2)

Iridescent bismuth crystal

Bismuth (Bi), commonly laboratory-grown and oxidized

Native silver fragment (probable)

Silver, Ag; possibly silver-bearing sulfide or plated metal

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

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

Amethyst cabochon jewelry

Amethyst, purple variety of quartz (SiO₂)

Dyed or coated quartz geode

Quartz geode; silicon dioxide (SiO₂), likely artificially color-enhanced

Turquoise-style beaded bracelet

Turquoise, hydrated copper–aluminum phosphate: CuAl₆(PO₄)₄(OH)₈·4H₂O; possibly dyed or composite beads

Faceted transparent gemstone, likely glass or cubic zirconia

Uncertain from image; possible cubic zirconia (zirconium dioxide, ZrO₂) or glass imitation

Clear quartz crystal pendant

Quartz (silicon dioxide, SiO₂)

Pink Granite

Phaneritic intrusive igneous rock with dominant Alkali Feldspar

One Pound Coin (UK)

Nickel-Brass Alloy (Cu-Zn-Ni)

Granite

Intrusive Felsic Igneous Rock

Granite

Intrusive Igneous Rock

Copper Ore

Native Copper (Cu) often found with Chalcocite (Cu2S) or Bornite (Cu5FeS4)

Ruby (set in a ring; possibly synthetic or imitation)

Corundum, Al₂O₃; red color is typically caused by chromium

Beryl (Aquamarine)

Be3Al2Si6O18

Malaysian 50 Sen Coin

Coinage (specific alloy unknown without metallurgical analysis, but typically brass or bronze for this denomination and era)

Granite

Felsic intrusive igneous rock

Beryl (Aquamarine)

Beryllium Aluminum Cyclosilicate (Be3Al2Si6O18)

Milky Quartz

Silicon Dioxide (SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Amethyst cabochon ring

Amethyst, purple quartz (SiO₂), colored primarily by iron-related defects and irradiation

Pyrite

Iron Sulfide (FeS2)

Quartz-bearing pyrite–chalcopyrite specimen

Pyrite (FeS₂), likely chalcopyrite (CuFeS₂), with quartz (SiO₂)

Bauxite

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

Granite

Felsic intrusive igneous rock

Granite

Intrusive Igneous Rock

Diamond-set letter “L” jewelry piece

Diamond (crystalline carbon, C) set in a metal mount; the metal is not identifiable from the image

Slag Glass (Cullet)

Amorphous Silica (man-made), primarily SiO2 with trace metal oxides