Mineral (Processed Alloy)

Road-surface aggregate (crushed stone)

Unidentifiable mixed lithic aggregate; likely basaltic/andesitic fragments with feldspar, quartz, and weathered rock

Dyed Blue Agate (Dragon Vein Agate)

Silicon Dioxide (SiO2) with artificial cobalt/organic dyes

Native gold-bearing sulfide specimen

Native gold (Au), likely intergrown with pyrite (FeS₂) or chalcopyrite (CuFeS₂)

Mixed Tumbled Gemstones (Agate, Aventurine, Pyrite, etc.)

Multiple (principally Silicon Dioxide SiO2 and Iron Disulfide FeS2)

Quartz pebble in concrete

Quartz (SiO₂), embedded in Portland-cement concrete

Native Copper

Copper (Cu)

Black Obsidian

Extrusive Volcanic Glass (primarily SiO2)

Dyed Fuchsia Tiger’s Eye

Pseudomorph of Quartz after Crocidolite (SiO2)

Copper-rich rock, likely native copper-bearing material

Native copper (Cu), possibly mixed with cuprite/iron oxides in a copper-rich matrix

Native gold (small nugget or grain)

Native gold, Au

Opalite

Synthetic glass / Opalized glass

Sulfide Ore (likely Galena and Sphalerite in Quartz)

Lead-Zinc Ore (PbS and ZnS)

Polished black obsidian

Volcanic glass; predominantly rhyolitic silica (SiO₂), with minor iron, magnesium, and alkalis

Chalcopyrite in Matrix

CuFeS2

Polished copper nugget

Native copper (Cu)

Pyrite-rich sulfide ore (likely pyrite with chalcopyrite)

Pyrite, FeS₂; possible chalcopyrite, CuFeS₂, and minor quartz or sphalerite

Native Copper

Native Copper (Cu)

Tumbled brown banded jasper

Microcrystalline quartz (SiO₂), commonly chalcedony with iron-oxide inclusions

Gold (Processed)

Gold (Au)

Likely silver-gray metallic ore fragment

Unidentified metallic mineral; possibly galena (PbS), but the image is insufficient for a confident identification

Satin spar gypsum (selenite)

Gypsum, CaSO₄·2H₂O

Iron Meteorite

Iron-Nickel Meteorite (primarily composed of kamacite and taenite alloys)

Dyed Pink Agate (Crackled)

Silicon Dioxide (SiO2) - Chalcedony variety

Vintage-style bracelet with likely black onyx and yellow-and-white jasper or agate cabochon

Onyx (cryptocrystalline quartz, SiO₂); central stone appears to be patterned jasper or agate (chalcedony, SiO₂), though identification from the image is uncertain

Asphalt aggregate (crushed stone in bitumen)

Artificial composite; predominantly crushed granite, basalt, limestone, and/or recycled aggregate bound by bitumen

Tumbled yellow-green chalcedony or serpentine

Microcrystalline quartz (SiO₂), possibly chrysoprase; alternative: serpentine-group mineral

Brick veneer, likely manufactured from clay-rich shale

Fired clay brick; chiefly aluminosilicate minerals, commonly mullite and glassy silicate phases after firing

Iron Meteorite

Siderite (Iron-Nickel Alloy)

Concretion

Sedimentary Concretion (e.g., Siderite or Ironstone)

Crushed Granite and Quartz Gravel

Composite Igneous and Silicate Rock Aggregate

Man-made Ceramic / Clay Figurine

Aluminosilicate Ceramic (Processed Clay)

Tumbled lavender quartz (likely lepidolite-bearing quartz or dyed quartz)

Quartz, SiO₂; possible lepidolite mica inclusions

Quartz (Tumbled/Water-worn)

Silicon Dioxide (SiO2)

United States Quarter Dollar

Cupronickel Clad Alloy (75% Copper, 25% Nickel over a 100% Copper core)

Ironstone (iron-oxide-rich rock)

Ferruginous sandstone or ironstone; likely composed chiefly of goethite and/or limonite, with quartz and clay

Cupronickel (on a 1981 Mexico 20 Pesos coin)

Copper-Nickel Alloy (Cu75Ni25)

Iron Meteorite

Siderite (Iron-Nickel Alloy)

Unidentified gray mineral/rock fragment

Indeterminate from image; possibly quartz-rich material or mica-bearing schist

Faceted blue gemstone ring, likely synthetic spinel or glass; identity uncertain

Possibly synthetic blue spinel (MgAl₂O₄) or laboratory sapphire (Al₂O₃); the clear side stones may be cubic zirconia or glass

Tumbled gray chalcedony (agate-like quartz)

Chalcedony, microcrystalline SiO₂

Mixed gemstone bead strand, likely including agate, quartz, turquoise, and sandstone beads

Varied silicate and copper-mineral materials; exact bead identities cannot be confirmed visually

Dyed Quartz Crystals

Silicon Dioxide (SiO2) with artificial pigment