Anthropogenic (Human Made) Sedimentary Like Material

Carved quartz skull, likely smoky quartz or gray chalcedony

Silicon dioxide (SiO₂), quartz or microcrystalline quartz

Tumbled chalcedony (likely moss or dendritic agate)

Microcrystalline quartz, SiO₂, with iron-oxide inclusions

Stone bead bracelet

Unidentified polished natural-stone beads; possibly wood-grain jasper, agate, or serpentine

Likely iron-rich rock or weathered metallic mineral fragment

Uncertain; possibly limonite/goethite or iron-bearing slag

Sandstone

Arenite

Carved labradorite fish

Labradorite, calcium-rich plagioclase feldspar (approximately (Ca,Na)(Al,Si)₄O₈)

Blue opalite (often sold as synthetic opal)

Opalite glass; amorphous hydrated silica if natural opal (SiO₂·nH₂O)

Sea Glass

Amorphous Silicon Dioxide (Man-made glass weathered by nature)

Chert (Flint)

Silicon dioxide (SiO2)

Green cabochon gemstone, likely nephrite jade

Nephrite jade—interlocking amphibole fibers, chiefly tremolite-actinolite, Ca₂(Mg,Fe)₅Si₈O₂₂(OH)₂

Slag (Industrial Glass)

Anthropogenic Amorphous Vitreous Silicate

Flint / Chert

Microcrystalline Quartz (SiO2)

Likely smoky quartz pendant

Smoky quartz, silicon dioxide (SiO₂), quartz variety colored by irradiation-related defects

Chert (Nodular or Massive Variety)

Cryptocrystalline Quartz (SiO2)

Green sea glass (likely bottle glass)

Human-processed soda–lime silicate glass; not a natural mineral or rock

Man-made Slag (Industrial Byproduct)

Anthropogenic Glassy Residue

Blue Goldstone

Aventurine Glass

Chert (likely flint)

Microcrystalline quartz, SiO₂

Quartz (likely Chalcedony or Chert)

Silicon Dioxide (SiO2)

Yellow faceted gemstone, likely citrine or synthetic glass

Citrine (quartz, SiO₂) is the leading natural possibility; visual identification is uncertain from the photograph

Heart-shaped faceted gemstone pendant

Likely yellow quartz (citrine) or synthetic yellow stone, set in metal with small clear accent stones

Likely blue glass or synthetic gemstone jewelry

Uncertain; possibly synthetic spinel, cubic zirconia, or blue glass

Small metallic-looking mineral/rock fragment

Indeterminate from image; possibly galena, hematite, or metallic slag

Chert (Arrowhead/Artifact Fragment)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Gemstone ring (stones not reliably identifiable from the image)

Likely faceted yellow stones and clear stones set in a metal band; species and treatments are indeterminate visually

Asphalt (Bituminous Pavement Bit)

Bitumen-bound aggregate (Petrochemical-bound composite)

Coquina (Fossiliferous Limestone)

Biogenic Limestone (Calcium Carbonate, CaCO3)

Crackle Agate / Dyed Quartz

SiO2 (Silicon Dioxide)

Flint / Chert

Microcrystalline quartz (SiO2)

Polished amethyst-bearing quartz

Quartz, SiO₂; purple coloration from irradiation and trace iron

Gold

Native Gold (Au)

Concrete Rubble with Aggregate

Hardened Portland Cement Paste with Coarse Aggregate

Flint (or Chert)

Cryptocrystalline Quartz (SiO2)

Concrete with Aggregate

Artificial Conglomerate (Cement and Aggregate)

Chert (Flint)

Microcrystalline Quartz (SiO2)

Chert (with nodule)

Microcrystalline Quartz (SiO2)

Blue-dyed Quartz Druzy

Silicon Dioxide (SiO2) with artificial pigment

Mixed quartz gemstone bead bracelet

Quartz, silicon dioxide (SiO₂), in varieties including smoky quartz, amethyst, rutilated quartz, and possibly tourmalinated quartz

Polished orbicular granite heart

Granite, commonly quartz–alkali feldspar–plagioclase–biotite granite; exact locality-dependent

Bismuth Crystal

Bismuth (Bi)

Aura Quartz (Anomalously Coated Quartz)

Silicon Dioxide (SiO2) treated with vaporized metals

Red-and-brown agate bead bracelet

Agate, a microcrystalline variety of quartz (SiO₂), likely colored chalcedony/carnelian