Mineral (Man Made Glass, Not Natural)

Quartz

Silicon dioxide (SiO₂)

Pearl

Calcium Carbonate (mostly Aragonite), CaCO3 (with conchiolin)

Diamond (in jewelry setting)

Carbon (C)

Diamond (in jewelry setting)

Adamantine Carbon (C)

Likely weathered granite or granitic gneiss fragment

Granite; primarily quartz, feldspar, and mica

Amethyst bead bracelet

Amethyst, purple quartz (SiO₂), with likely dyed or heat-treated agate/carnelian beads

Exposed aggregate concrete (stone-chip surface)

Portland-cement concrete containing natural aggregate; not a natural rock

Blue gemstone bead bracelet, likely lapis lazuli or dyed stone

Uncertain from image; possible lazurite-bearing lapis lazuli (Na₃Ca(Si₃Al₃)O₁₂S) or dyed quartz/glass imitation

Polished stromatolite (likely fossilized microbial mat)

Fossil stromatolite; chiefly microcrystalline quartz (SiO₂), commonly replacing carbonate

Inlaid stone ring (likely jasper or agate)

Likely microcrystalline quartz (chalcedony, SiO₂), possibly jasper, with decorative mineral inlays

Granite

Phaneritic Plutonic Felsic Rock (SiO2, KAlSi3O8, NaAlSi3O8, CaAl2Si2O8)

Diamond

C (Pure Carbon)

Natural Pearl (appearing in a jewelry setting)

Calcium Carbonate (mostly Aragonite), CaCO3 with Conchiolin

Green Aura Quartz (Titanium treated Kyanite or Quartz)

Silicon Dioxide (SiO2) or Aluminum Silicate (Al2SiO5) with Titanium/Metal Oxide coating

Sandstone (Ferruginous)

Arenite (SiO2 with Fe2O3 inclusions)

Chert (Flint)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Flaked stone projectile point

Likely worked chert or fine-grained silicified shale; exact lithology cannot be confirmed from the image

Sandstone

Sedimentary Rock (Quartz Sandstone)

Diamond (in a jewelry setting)

Cubic Carbon (C)

Pearl (Biogenic)

Nacre / Calcium Carbonate (CaCO3)

Likely weathered iron-rich rock or slag fragment

Uncertain; possibly limonite/goethite-rich material (FeO(OH)·nH₂O)

Tumbled blue stone, likely blue calcite or dyed stone

Probably calcite (CaCO₃); exact identification is uncertain from the blurred image

Chalcedony / milky quartz flake

Microcrystalline quartz (SiO₂), likely chalcedony; possibly a worked quartzite or chert fragment

Beaded blue-and-green gemstone jewelry

Likely dyed or treated chalcedony/agate and green aventurine or glass-like stone; exact identification requires testing

Sandstone (likely Fossilized Wood or Concrete Simulacrum)

Arenite / Silicified Wood / Anthropogenic Concrete

Pearl-and-gemstone insect brooch

Pearl: nacre (aragonite, CaCO₃); colored stones are likely synthetic or natural corundum/spinel/glass, not determinable from the image

Man-made Blank Ammunition (Brass)

CuZn (Cartridge Brass - roughly 70% Copper, 30% Zinc)

Sandstone Pebble

Ferruginous Sandstone (SiO2 with Fe2O3)

Polished rutilated quartz cabochon

Quartz (SiO₂) with rutile inclusions (TiO₂)

Green aventurine bead bracelet

Quartz (SiO₂), typically green quartzite/aventurine colored by fuchsite mica or other inclusions

Obsidian (likely snowflake or banded variety)

Volcanic glass, primarily SiO₂

Slag Glass (Cullet)

Amorphous Silicon Dioxide (SiO2) with metal oxide colorants

Rounded pink granite cobble

Granite, chiefly quartz–alkali feldspar–plagioclase–biotite

Diamond

Carbon (C)

Bismuth Crystal

Bismuth (Bi)

Polished dendritic agate cabochon (likely agate or jasper)

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

Synthetic Marbled Aggregate (Footwear Component)

Ethylene-vinyl acetate (Croslite™)

Smoky Quartz

Silicon Dioxide (SiO2)

Carnelian cabochon pendant

Carnelian, orange-red chalcedony (microcrystalline quartz, SiO₂)

Bismuth crystal

Bismuth (Bi), synthetic laboratory-grown crystal

Fossil or modern bivalve shell

Calcium carbonate shell, likely aragonite (CaCO₃); exact species cannot be determined from the image

Black Obsidian

Obsidian (Volcanic Glass, SiO2 + impurities)