Man Made Glass (Not A Natural Rock Or Mineral)

Black tumbled stone, possibly obsidian

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

Asphalt (Road Aggregate)

Bituminous Conglomerate / Asphalt Concrete

Polished blue glassy mineral specimen, likely sodalite or blue aventurine

Most consistent with sodalite (Na₈Al₆Si₆O₂₄Cl₂), though dyed quartzite or blue glass cannot be excluded from the photograph

Opalite

Man-made glass (traditionally simulated Opal)

Opalite (likely imitation opal glass)

Man-made opalescent glass; not a natural mineral (often sold as opalite)

Likely blue-green glassy slag or a weathered mineral fragment

Unidentified; the image does not show diagnostic features sufficient for a mineral identification

Opalite crescent pendant

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

Colorless quartz crystal (likely quartz fragment)

Quartz, silicon dioxide (SiO₂)

Aura Quartz (Titanium/Rainbow Quartz)

SiO2 (Silicon Dioxide) with metallic coating

Opalite

Synthetic Opalized Glass (SiO2 + additives)

Blue Goldstone

Goldstone (artificial glass)

White pebble, likely quartz or calcite

Indeterminate from image; possible microcrystalline quartz (SiO₂) or calcite (CaCO₃)

Agate and millefiori glass jewelry

Agate: microcrystalline quartz (SiO₂); millefiori element appears to be man-made glass

Possible obsidian or slag glass

Volcanic glass, primarily SiO₂; alternatively industrial iron-rich glassy slag

Sea Glass

Amorphous silicon dioxide (Man-made glass weathered by wave action)

Cullet Glass (Slag Glass)

Amorphous Silicon Dioxide (Industrial Byproduct)

Beads (likely glass or man-made material)

N/A (artificial material)

Cullet Glass (Slag)

Amorphous Silicon Dioxide (Man-made)

Opalite

Synthetic Glass (typically Silica/Magnesium based with metal additives)

Opalite

Opalescent Glass (SiO2 + coloring agents)

Cubic Zirconia (Jewelry Setting)

Zirconium Dioxide (ZrO2)

Concrete / Conglomerate (Man-made)

Artificial Conglomerate (Cementitious Composite)

Opalite

Synthetic Glass (Simulated Opal)

Faceted glass-like gemstone (likely synthetic quartz or cubic zirconia)

Identification uncertain; possibilities include synthetic quartz (SiO₂) or cubic zirconia (ZrO₂)

Not a geological specimen

N/A (man-made object)

Polished black pebble, likely basalt

Basalt, a fine-grained mafic volcanic rock composed mainly of plagioclase feldspar and pyroxene, commonly with olivine

Silicon Carbide (Carborundum)

Silicon Carbide (SiC) / Moissanite (natural)

Sea Glass

Amorphous Silicon Dioxide (SiO2)

Tumbled white chalcedony (likely milky quartz)

Chalcedony, microcrystalline quartz (SiO₂)

Tumbled milky quartz pebble

Quartz (silicon dioxide, SiO₂), opaque-to-translucent milky variety

Opalite

Synthetic Opalite Glass (Silicon Dioxide)

Opalite (likely man-made opalescent glass)

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

Conglomerate

Conglomerate (clastic sedimentary rock)

Aventurine Quartz

Silicon Dioxide (SiO2) with Fuchsite inclusions

Asphalt (Bituminous Pavement)

Bituminous mix (Aggregates with Bitumen binder)

Cullet (Slag Glass)

Amorphous Silica (SiO2) with various metal oxide colorants

Blue Obsidian

Volcanic Glass (SiO2 with inclusions)

Diamond

Native Carbon (C)

Goldstone (aventurine glass)

Man-made copper-bearing glass; not a natural mineral (commonly sold as blue/brown goldstone)

Green glass cabochon or tumbled stone

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

Tumbled Clear Quartz/Rock Crystal

Silicon Dioxide (SiO2)

Polished milky quartz (likely quartz worry stone or wand)

Quartz, silicon dioxide (SiO₂)