Mineraloid (Human Made Geological Specimen)

Black Obsidian

Obsidian (Amorphous Silicon Dioxide)

Black Obsidian

Obsidian (Volcanic Glass, ~70% SiO2)

Opalite

Synthetically produced glass (Silicon Dioxide with metallic inclusions)

Orange calcite

Calcite (CaCO₃), likely translucent orange calcite

Black cabochon pendant, likely onyx or black glass

Most likely black chalcedony (microcrystalline quartz, SiO₂); the surrounding stones may be cubic zirconia or glass

Fossilized Brain Coral

Diploria labyrinthiformis (Fossilized)

Blue sea glass or blue glassy mineral fragment

Uncertain; likely man-made soda-lime glass, not a natural mineral

Chert (likely flint)

Microcrystalline quartz, SiO₂

Porous limestone (likely fossiliferous or weathered limestone)

Calcite-rich limestone; chiefly calcium carbonate (CaCO₃)

Chert

Microcrystalline quartz (SiO2)

Inukshuk Rock Sculpture (composed of Granite, Slate, and Amethyst)

Silicon Dioxide (Amethyst portion, SiO2) with mixed silicate rock assemblage

Tumbled dark metallic mineral specimen

Likely hematite or magnetite; identification is uncertain from the photograph

Chert (Chalcedony/Agate)

Microcrystalline Quartz (SiO2)

Obsidian

Volcanic Glass (Primary composition: SiO2 - Silicon Dioxide)

Pink quartz bead necklace/strand

Quartz, silicon dioxide (SiO₂), likely rose quartz or pink chalcedony; exact identification is uncertain from the image

N/A - Man-made object (Jewelry Chain)

Antiqued or Oxidized Metal Chain (often Steel or Brass)

Obsidian

Volcanic Glass (Silicon Dioxide with impurities)

Small tumbled blue-green stone, possibly chrysocolla or turquoise

Indeterminate copper-bearing mineral; possible chrysocolla (Cu₂H₂Si₂O₅(OH)₄·nH₂O) or turquoise (CuAl₆(PO₄)₄(OH)₈·4H₂O)

Mahogany Obsidian

Volcanic Glass (predominantly SiO2 with inclusions of Hematite or Magnetite)

Tumbled magnetite (likely)

Magnetite, Fe₃O₄

Pyrite

Iron Sulfide (FeS2)

Chert (Jasper / Quartz pebble)

Microcrystalline Quartz (SiO2)

Black obsidian

Volcanic glass, primarily rhyolitic silica glass (SiO₂-rich, noncrystalline)

Mixed polished/tumbled stones; likely blue calcite, red carnelian, and gray/blue quartz or agate

Probable calcite (CaCO₃), chalcedony/quartz (SiO₂), and iron-colored chalcedony

Obsidian

Obsidian (volcanic glass), primarily SiO2 (silicon dioxide)

Carved nephrite jade Buddha

Nephrite jade, an interlocking amphibole aggregate dominated by tremolite–actinolite, Ca₂(Mg,Fe)₅Si₈O₂₂(OH)₂

Honey calcite

Calcite (calcium carbonate, CaCO₃)

Chert (Nodular or Massive Variety)

Cryptocrystalline Quartz (SiO2)

Chert (Flint)

Microcrystalline quartz (SiO2)

Slag

Metallurgical Slag

Chert

Microcrystalline quartz (SiO2)

Snowflake Obsidian

Volcanic glass with Cristobalite inclusions (mostly SiO2)

Chert (Honey Chert / Flint)

Silicon Dioxide (SiO2)

Obsidian

Volcanic Glass (SiO2 rich)

White Opal (Common)

Hydrated Silica (SiO2·nH2O)

Cut faceted gemstone, possibly diamond or quartz

Uncertain from the blurred image; diamond is crystalline carbon (C), while quartz is silicon dioxide (SiO₂)

Green sea glass (likely bottle glass)

Man-made soda-lime silicate glass; not a natural mineral

Tumbled quartz-rich sandstone

Quartz arenite (siliciclastic sandstone), likely iron-stained

N/A

Dyed or coated quartz/amethyst specimen (likely)

Quartz, SiO₂; purple portion may be amethyst, iron-bearing quartz

Common Opal with Host Rock

Opal (Hydrated silica, SiO2·nH2O)

Titanium Aura Quartz

Titanium-coated Silicon Dioxide (SiO2)