Mineraloid (Man Made Glass)

Green glass sphere/marble

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

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

Rock crystal (clear quartz), possibly cloudy quartz

Quartz, silicon dioxide (SiO₂)

Transit Token (RTD Denver)

Nickel-plated brass or bronze alloy (Cu-Sn-Zn-Ni)

Mystic Topaz (Treated Quartz or Topaz)

Aluminum silicate fluoride hydroxide [Al2SiO4(F,OH)2] with thin-film metallic coating

Sandstone Concretion

Limonitic Sandstone Concretion

Asphalt (Road Aggregate)

Bituminous conglomerate

Tumbled milky quartz pebble

Quartz (silicon dioxide, SiO₂), likely milky quartz

Rock crystal quartz fragments

Quartz (silicon dioxide, SiO₂)

Polished labradorite sphere

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

Blue Goldstone

Synthetic Avanturine Glass (or Aventurine Glass)

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

Opalite (likely man-made opalescent glass)

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

Green sea glass (likely bottle glass)

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

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

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

Ferrous Slag

Iron/Steel Slag (Complex Calcium-Alumino-Silicates)

Crushed Stone (Likely Limestone or Granite)

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

Sea Glass

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

Aura Quartz (Rainbow Quartz)

Silicon Dioxide (SiO2) with metallic vapor coatings

Milky quartz (likely quartz crystal fragment)

Quartz, silicon dioxide (SiO₂)

Concrete Rubble with Aggregate

Hardened Portland Cement Paste with Coarse Aggregate

Concrete Paver (Artificial Cementitious Rock)

Hydrated Portland Cement Aggregate

Unidentifiable Rock Fragment

Asphalt Concrete (Bituminous Conglomerate)

Anthropogenic Bituminous Conglomerate

Concrete

Anthropogenic Conglomerate

Polished labradorite pendant

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

Citrine Quartz

Citrine (Silicon Dioxide, SiO2)

Colorless quartz crystal (likely quartz fragment)

Quartz, silicon dioxide (SiO₂)

Polished silver sheen obsidian heart

Obsidian (volcanic glass), primarily rhyolitic silica-rich glass

Titanium-coated Metal Cube (Man-made Fidget Toy)

Titanium-anodized or electroplated alloy (e.g., Ti-coated Zinc or Aluminum)

Chert Arrowhead (Projectile Point)

Microcrystalline Quartz (Chert or Flint)

Blue Goldstone

Goldstone (artificial glass)

Green sea glass (likely bottle glass)

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

Strawberry Quartz

Silicon Dioxide (SiO2) with Hematite/Goethite inclusions

Pearl

Calcium carbonate (CaCO3) - mainly Aragonite with Conchiolin

Aggregate Concrete

Anthropogenic Conglomerate (Technosol)

Asphalt Concrete

Bituminous Concrete

Titanium Aura Quartz

Titanium bonded Silicon Dioxide (SiO2 + Ti)

Green Glass Slag

Amorphous Silicon Dioxide (SiO2) with metal oxide impurities

Faceted clear gemstone, likely quartz or glass imitation

Most likely quartz (SiO₂); exact identification requires refractive-index and hardness tests