Man Made Silicate (Anthropogenic Glass)

Green Aventurine

Silicon Dioxide (Quartz with Fuchsite inclusions), SiO2

Clear quartz crystal (likely)

Quartz, silicon dioxide (SiO₂)

Tumbled clear quartz (rock crystal)

Quartz, silicon dioxide (SiO₂)

Tumbled opalite (likely man-made glass)

Opalite glass; a synthetic opalescent glass, not a natural mineral species

Chert (Arrowhead Shard)

Microcrystalline silica (SiO2)

Opalite crescent pendant

Opalite (man-made opalescent glass; not a natural mineral)

Opalite

Synthetically produced glass (Silicon Dioxide with metallic inclusions)

Slag (Industrial Glass)

Artificial Vitreous Silicate

Clear quartz crystal (likely)

Quartz, silicon dioxide (SiO₂)

Opalite (Man-made Glass)

Synthetic Silicon Dioxide Glass (SiO2 + metal oxides)

Blue tumbled glass-like specimen; likely blue slag glass

Likely man-made glass (silicate glass), not a natural mineral; exact material cannot be confirmed from the image

Goldstone (Red)

Aventurine Glass (Cupriferous glass)

Moldavite

Tektite (Impact Glass), ~80% SiO2 + Al2O3

Quartz (likely milky quartz or quartz glass-like fragment)

Quartz, silicon dioxide (SiO₂)

Libyan Desert Glass

Tektite (high-silica impact glass), SiO2

Chert (Arrowheads)

Microcrystalline Quartz (SiO2)

Blue opalite glass (likely man-made)

Opalite glass; a silica-based amorphous glass, not natural opal

Opalite (Man-made Glass)

Fused glass (typically made of dolomite and metal opacifiers)

Black tumbled stone, possibly obsidian

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

Libyan Desert Glass

Libyan Desert Glass (SiO2 with trace elements)

Clear quartz sphere

Quartz (silicon dioxide, SiO₂)

Pet Rock (Man-made Quartzite or Granite Cobble)

Silicon dioxide (SiO2) mixture; commonly composed of Quartz, Feldspar, and Mica

Red Slag Glass

Amorphous Silica (Industrial byproduct with metallic oxide dopants)

Tumbled clear quartz (rock crystal)

Quartz, silicon dioxide (SiO₂)

Clear quartz tumbled stone

Quartz (silicon dioxide, SiO₂)

Opalite

Synthetic Opalised Glass

Ferrochrome Slag

Anthropogenic silicate/oxide glass (Complex silicate matrix with Cr-Fe-Si inclusions)

Terrazzo (with Marble and Granite fragments)

Cementitious or resinous composite containing Calcium Carbonate (CaCO3) and Silicates

Obsidian (Blue)

Volcanic Glass (SiO2)

Strawberry Quartz

Silicon Dioxide (SiO2) with Hematite or Goethite inclusions

Tumbled milky quartz pebble

Quartz (silicon dioxide, SiO₂)

Opalite

Synthetic Opalized Glass

Blue cabochon gemstone, likely synthetic glass or dyed stone

Indeterminate from image; possible glass, synthetic spinel, sodalite, or lapis lazuli

Polymictic conglomerate or breccia (possibly concrete-like aggregate)

Lithified polymictic gravel; clasts may include basalt, granite, quartzite, and other silicates

Tumbled opalite (likely man-made glass)

Opalite, a trade name for opalescent glass; not natural opal

Blue glassy gemstone cabochon, likely dyed chalcedony or glass

Uncertain; possible dyed chalcedony (microcrystalline quartz, SiO₂)

Exposed Aggregate Concrete (Pea Gravel)

Concrete with Siliceous Alluvial Gravels

Likely clear quartz pebble or glassy quartz fragment

Quartz (silicon dioxide, SiO₂)

Tumbled gray stone, likely quartz-rich pebble

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

Blue Goldstone

Man-made glass with suspended copper, cobalt, or manganese particles

Man-made Carved Stone (Scream Mask/Skull motif)

Carved Soapstone or Serpentine-rich rock

Opalite

Synthetic Glass (Simulated Moonstone/Opal)