Man Made Object (Coin)

Polished milky quartz (likely quartz worry stone or wand)

Quartz, silicon dioxide (SiO₂)

Metal Chain (Likely Steel or a Steel Alloy)

Steel (primarily iron and carbon); specific alloy unknown

Polished labradorite sphere

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

Sea Glass

Silicon dioxide (mostly)

Red-orange cabochon, likely carnelian or glass imitation

Carnelian: chalcedony (microcrystalline SiO₂), commonly iron-colored

Blue crystal pendant (likely blue glass or synthetic crystal)

Not identifiable from the image; possibly synthetic quartz or glass, rather than a natural mineral

Quartz pebble (Quartztite fragment)

Silicon Dioxide (SiO2)

Sea Glass

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

Black glassy fragment, likely obsidian or industrial glass

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

Stainless Steel (Polished)

Ferrous Alloy containing Iron (Fe), Chromium (Cr), and Carbon (C)

Polished black stone, likely obsidian

Obsidian (volcanic glass; mostly silica-rich rhyolitic composition)

Black tumbled stone, possibly obsidian

Obsidian (volcanic glass; predominantly SiO₂), identification uncertain from image

Green sea glass (likely bottle glass)

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

Cobalt Blue Glass / Cullet Glass

Silicon dioxide (Amorphous man-made glass)

Chert (Arrowheads)

Microcrystalline Quartz (SiO2)

Exposed Aggregate Concrete (Pea Gravel)

Concrete with Siliceous Alluvial Gravels

Blue chalcedony (likely dyed or treated)

Microcrystalline quartz, SiO₂ (chalcedony)

Sandstone Concretion

Clastic sedimentary rock (primarily Quartz SiO2)

Concrete Fragment

Hardened Portland cement and mineral aggregate

Milky quartz (likely quartz crystal fragment)

Quartz, silicon dioxide (SiO₂)

Opalite

Synthetic Opalite Glass / Opalized Glass

Asphalt Concrete

Bituminous conglomerate

Cullet Glass (Slag Glass)

Amorphous Silicon Dioxide (SiO2) with metallic oxide impurities

Slag (Industrial Byproduct)

Artificial silicate/iron byproduct

Tumbled milky chalcedony (likely common opalite-like quartz)

Chalcedony, microcrystalline SiO₂; possibly pale common opal, hydrated SiO₂·nH₂O

Polished obsidian

Volcanic glass; predominantly rhyolitic SiO₂

Green Obsidian Sphere (man-made glass)

Vitreous Silica with Chromium/Iron additives

Blue-green faceted gemstone, possibly glass or synthetic material

Not identifiable from the image; possible synthetic spinel or glass

Asphalt (Road Aggregate)

Bituminous conglomerate

Mystic Topaz (Treated Quartz or Topaz)

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

Sandstone Concretion

Limonitic Sandstone Concretion

Terrazzo (Man-made Composite)

Cementitious or Resin-bound Lithic Composite

Blue glass-like bead or gemstone keychain ornament

Indeterminate; likely cobalt-blue glass or synthetic blue spinel, not identifiable as a natural mineral from the image

Opalite

Synthetic Opalite (Man-made glass)

Opalite

Man-made Glass (SiO2 + additives)

Blue Slag Glass

Man-made Silicon Dioxide (Amorphous)

Cullet Glass (Slag)

Amorphous Silicon Dioxide (Man-made)

Green Sea Glass

Man-made silicate glass (weathered)

Crushed Stone (Likely Limestone or Granite)

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

Tumbled black stone, likely black obsidian

Obsidian; volcanic glass, typically rhyolitic composition (SiO₂-rich)

Blue Apatite

Apatite (Calcium Phosphate) - Ca5(PO4)3(F,Cl,OH)

Likely ironstone or weathered iron-rich rock

Hematite/goethite-bearing ferruginous concretion; exact identification requires testing