Not A Natural Rock (Man Made Composite)

Titanium Amethyst Geode

Silicon Dioxide (SiO2) with Titanium/Metal Vapor Deposition Layer

Green Glass (often marketed as 'Obsidian' or 'Green Quartz')

Amorphous Silica (SiO2) with copper or chromium additives

Opalite

Man-made Glass (Synthetic Opalized Glass)

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

One Pound Coin (UK)

Nickel-Brass Alloy (Cu-Zn-Ni)

Dyed Agate

Chalcedony (SiO2)

Blue glassy gemstone cabochon, likely dyed chalcedony or glass

Uncertain; possible dyed chalcedony (microcrystalline quartz, SiO₂)

Concrete aggregate surface

Human-made cementitious composite; primarily calcium-silicate-hydrate cement with mixed silicate aggregate

Concrete Rubble with Aggregate

Hardened Portland Cement Paste with Coarse Aggregate

Obsidian (Blue)

Volcanic Glass (SiO2)

Man-made Slag (Industrial Byproduct)

Anthropogenic Glassy Residue

Tumbled milky quartz pebble

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

Aura Quartz (Rainbow Quartz)

Silicon Dioxide (SiO2) with metallic vapor coatings

Goldstone (aventurine glass)

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

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

Carved Soapstone or Serpentine-rich rock

Blue cabochon gemstone, likely synthetic glass or dyed stone

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

Aura Rose Quartz

SiO2 (Silicon Dioxide with Titanium/Gold coating)

Opalite crescent pendant

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

Aura Quartz

Titanium-coated Silicon Dioxide (SiO2)

Diamond

Carbon (C)

Metal Chain Belt with Square Plates

Not applicable (man-made)

Tumbled white chalcedony (likely milky quartz)

Chalcedony, microcrystalline quartz (SiO₂)

Cubic Zirconia (Diamond Simulant)

Zirconium Dioxide (ZrO2)

Titanium Aura Quartz (Bismuth-coated Druzy)

Silicon Dioxide (SiO2) with Titanium/Metal vapor coating

Goldstone

Avventurina (Man-made Glass with Copper inclusions)

Concretion (Sandstone)

Carbonate-cemented Sandstone Concretion

Opalite

Synthetic Glass (Simulated Opal)

Porcelain (Stoneware Ceramic)

Mullite / Silica-glass composite (Al6Si2O13)

Man-made Glass (Tumbled/Shaped)

Amorphous Silicon Dioxide (SiO2) with metal oxide colorants

Blue Slag Glass

Man-made Silicon Dioxide (Amorphous)

Clear faceted gemstone, likely synthetic cubic zirconia

Cubic zirconia (zirconium dioxide, ZrO₂); visual identification is not definitive and diamond or synthetic moissanite are alternatives

Opalite

Synthetic Glass, SiO2 base with metallic inclusions

Green Sea Glass

Man-made vitreous material (silica glass)

Colorless faceted gemstone (likely cubic zirconia)

Cubic zirconia, zirconium dioxide (ZrO₂); possibly synthetic quartz or glass imitation

Polished black stone, likely black obsidian

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

Asphalt Concrete

Bituminous Concrete (Anthropic Rock)

Polished milky quartz (likely quartz worry stone or wand)

Quartz, silicon dioxide (SiO₂)

White quartz pebble

Quartz (SiO₂), likely milky quartz

Opalite

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

Opalite

Synthetic opalescent glass

Aqua Aura Quartz

Silicon Dioxide (SiO2) bonded with Gold (Au)

Sandstone

Sandstone (clastic sedimentary rock composite)