Man Made Silicate (Anthropogenic Glass)

Blue Obsidian (Cullet Glass)

Silicon Dioxide (Amorphous Glass)

Green sea glass or tumbled green quartz (uncertain)

Likely quartz (SiO₂) if natural; alternatively man-made soda-lime glass

Clear quartz fragment (rock crystal)

Quartz, silicon dioxide (SiO₂)

Green glass sphere/marble

Soda-lime glass (primarily SiO2, Na2O, CaO)

Green sea glass or green glass-like tumbled material

Amorphous silicate glass; likely anthropogenic soda-lime glass, not a natural mineral

Decorative mosaic cross containing mixed rock and glass fragments

Polychrome aggregate; likely quartz, feldspar, marble, granite, and assorted colored glass

Opalite

Synthetic Glass (Hydrated Crystalline Silicon Dioxide simulation)

Asphalt Concrete

Bituminous conglomerate

Opalite

Man-made Synthetic Glass (Silicon Dioxide with metal additives)

Black glassy fragment, likely obsidian or industrial glass

Volcanic glass (obsidian), chiefly amorphous SiO₂; identification uncertain from image

Sandstone (likely Fossilized Wood or Concrete Simulacrum)

Arenite / Silicified Wood / Anthropogenic Concrete

Blue Goldstone

Aventurine Glass

Asphalt Concrete

Bituminous Concrete / Asphaltic Composite

Asphalt (Bituminous Concrete)

Bituminous mix / Anthropogenic conglomerate

Rock crystal (clear quartz), possibly cloudy quartz

Quartz, silicon dioxide (SiO₂)

Blue Goldstone

Synthetic Avanturine Glass (or Aventurine Glass)

Opalite

Synthetic Opalised Glass

Green Aventurine

Quartzite with Fuchsite inclusions (SiO2 + K(Al,Cr)2(AlSi3O10)(OH)2)

Polished white chalcedony or quartz pendant

Microcrystalline quartz (chalcedony), SiO₂; exact identification is uncertain from the image

Polished labradorite sphere

Labradorite, calcic plagioclase feldspar ((Ca,Na)(Al,Si)₄O₈)

Asphalt (Road Aggregate)

Bituminous conglomerate

Small greenish crystal/mineral fragment

Indeterminate; possibly olivine, quartz, or a green gemstone fragment

Pyrite in Quartz (Drill Core)

Silicon Dioxide (SiO2) with Iron Sulfide (FeS2) inclusions

Tumbled milky quartz pebble

Quartz (silicon dioxide, SiO₂), likely milky quartz

Opalite (likely man-made opalescent glass)

Opalite; not a true mineral, typically synthetic opalescent glass (silica-based)

Sea Glass

Amorphous silicon dioxide (SiO2) - Man-made glass tumbled by nature

Chert Arrowhead

Microcrystalline Quartz (SiO2)

Cullet Glass (sometimes mistaken for Blue Obsidian or Slag)

Amorphous Silicon Dioxide (SiO2) with chemical additives (e.g., Cobalt for blue color)

Sandstone Concretion

Limonitic Sandstone Concretion

Opalite

Synthetic glass (SiO2 + metal additions)

Slag (Industrial Glass/Metal)

Ferrous slag or Glassy silicate byproduct

Rock crystal quartz fragments

Quartz (silicon dioxide, SiO₂)

Crushed Stone (Likely Limestone or Granite)

Calcium Carbonate (CaCO3) for Limestone / Quartz and Feldspar for Granite

Milky quartz (likely quartz crystal fragment)

Quartz, silicon dioxide (SiO₂)

Iron Slag

Ferrous slag (primarily silicates and oxides of calcium, iron, and magnesium)

Green obsidian (likely molded or heat-treated glass-like specimen)

Volcanic glass; predominantly rhyolitic composition (silica-rich amorphous SiO₂)

Goldstone (brown goldstone)

Man-made aventurine glass, typically copper-bearing silica glass

Opalite

Synthetic Opalite Glass (Silicon Dioxide)

Ferrosilicon Slag (Industrial Vitrified Glass)

Vitreous Silicate Residue

Luminous Stone (Glow-in-the-dark Synthetic/Man-made Stone)

Strontium Aluminate tinted glass or resin (Crystalline silicate/oxide mix)

Aura Quartz (Rainbow Quartz)

Silicon Dioxide (SiO2) with metallic vapor coatings

Polished labradorite pendant

Labradorite, a calcium-rich plagioclase feldspar (approximately NaAlSi₃O₈–CaAl₂Si₂O₈)