Man Made Glass

Likely tumbled or cut quartz/chalcedony fragment

Silicon dioxide (SiO₂), probably microcrystalline quartz or quartz

Obsidian (likely black volcanic glass)

Obsidian; primarily amorphous volcanic silica glass, approximately SiO₂-rich rhyolitic composition

Rock crystal quartz fragments

Quartz (silicon dioxide, SiO₂)

Raw quartz crystal

Quartz (silicon dioxide, SiO₂), likely milky or included quartz

Strawberry Quartz

Silicon Dioxide (SiO2) with Hematite/Goethite inclusions

Blue Sapphire (Synthetic or Man-made Glass Imitation)

Corundum (Al2O3) if natural; Lead-glass or Spinal if synthetic

Likely clear quartz crystal or glass-like gemstone

Quartz, silicon dioxide (SiO₂); exact identification is uncertain from the strongly magenta-lit image

Polished obsidian

Volcanic glass; predominantly rhyolitic SiO₂

Polished white chalcedony or quartz pendant

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

Polished black stone, likely black obsidian

Obsidian (volcanic glass), chiefly silica-rich rhyolitic composition

Iron Slag

Iron/Steel Slag (Ferrosilicate Glass)

Likely polished quartz or glass-like mineral cabochon

Probably quartz (SiO₂), though the image cannot exclude man-made glass

Tumbled gray stone, likely quartz-rich pebble

Probable microcrystalline quartz/chalcedony (SiO₂), possibly gray jasper or quartzite

Green Aventurine

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

Slag

Ferrous Slag (Amorphous calcium-magnesium-aluminum silicates)

Tumbled milky quartz

Quartz (silicon dioxide, SiO₂)

Libyan Desert Glass

Impact-melt silica glass (SiO2 + traces of Al, Fe, Ti)

Opalite

Synthetic Opalized Glass (SiO2 + additives)

Opalite

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

Cullet Glass (Slag Glass)

Amorphous Silicon Dioxide (SiO2) with metallic oxide impurities

Tumbled black obsidian (likely)

Volcanic glass; chiefly silica-rich rhyolitic glass (SiO₂)

Opalite (a synthetic glass, often confused with Opal)

Silicon dioxide glass (SiO2nH2O, for natural opal)

Blue Impression Jasper beads

Impression jasper (microcrystalline quartz/chalcedony), chiefly SiO₂, with iron-oxide and other mineral inclusions

Blue chalcedony (likely dyed or treated)

Microcrystalline quartz, SiO₂ (chalcedony)

Colorless quartz crystal (likely quartz fragment)

Quartz, silicon dioxide (SiO₂)

Tumbled milky chalcedony (likely common opalite-like quartz)

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

Red glassy cabochon, likely synthetic ruby or red glass

Uncertain; possible synthetic corundum (Al₂O₃, chromium-colored) or man-made glass

Aventurine

Quartz containing inclusions of Fuchsite (SiO2 + K(Al,Cr)2AlSi3O10(OH)2)

Slag Glass

Anthropogenic Amorphous Silicon Dioxide

Tumbled black stone, likely black obsidian

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

Small clear crystal, possibly quartz or glass-like gemstone

Uncertain; likely quartz (SiO₂), but the image is insufficient to exclude man-made glass or cubic zirconia

Green glass cabochon or tumbled stone

Indeterminate; likely man-made glass, possibly aventurine glass rather than a natural mineral

Polished green-and-black banded cabochon (likely malachite imitation or dyed agate)

Uncertain; possible malachite (Cu₂CO₃(OH)₂), banded agate (SiO₂), or man-made glass

Blue Goldstone

Synthetic glass with cobalt and copper inclusions

Slag Glass

SiO2 (Silicon Dioxide) with impurities

Blue Goldstone

Aventurine Glass

Blue slag glass or dyed glass-like industrial material

Amorphous silicate glass; likely copper-bearing blue slag, but possibly colored man-made glass

Blue Goldstone

Aventurine Glass (SiO2 with Cobalt/Copper inclusions)

Crackle Glass (Simulated Gemstone)

Amorphous Solid (SiO2)

Blue Goldstone

Synthetic Aventurescent Glass (Cobalt-doped soda-lime glass)

Blue Goldstone

Aventurine glass (Synthetic borosilicate glass with cobalt and metallic inclusions)

Blue Goldstone

Synthetic glass with copper or cobalt/manganese inclusions