Polished black pebble, possibly obsidian
Volcanic glass (obsidian), likely; identification is tentative from the image
Category
Browse mineral (man made glass) specimens identified by the Rock Identifier community.
Polished black pebble, possibly obsidian
Volcanic glass (obsidian), likely; identification is tentative from the image
Man-made Polished Porcelain Tile (Artificial Geologic Lookalike)
Fused Silicate Ceramic with Alumina (Synthetic Kaolinite derivative)
Concrete
Anthropogenic Conglomerate
Polished black stone, likely black obsidian
Volcanic glass; predominantly rhyolitic silica glass (SiO₂-rich)
Iron Slag (Industrial Byproduct)
Anthropogenic Vitrification Product/Ferrous Slag
Goldstone (Red)
Aventurine Glass (SiO2 + Cu)
Unidentifiable Rock Fragment
Ferrochrome Slag
Anthropogenic slag (Fe-Cr alloy waste)
Iron-rich slag or ironstone; appearance is not diagnostic
Likely iron-oxide-rich material (hematite, Fe₂O₃, and/or magnetite, Fe₃O₄); possibly smelting slag
Rainbow Hematite Ring
Iron(III) oxide (Fe2O3) with thin-film coating
Goldstone (Brown/Gold variety)
Aventurine Glass (SiO2 with Copper inclusions)
Asphalt Concrete
Bituminous Concrete (Anthropic Rock)
Concrete with Aggregate
Artificial Conglomerate (Cement and Aggregate)
Obsidian (likely black volcanic glass)
Obsidian; primarily amorphous volcanic silica glass, approximately SiO₂-rich rhyolitic composition
Transit Token (RTD Denver)
Nickel-plated brass or bronze alloy (Cu-Sn-Zn-Ni)
Opalite
Synthetic Fluorescent Glass (SiO2 + impurities)
Blue goldstone
Man-made aventurine glass containing metallic copper particles; not a natural mineral
Polished white calcite sphere (identification tentative)
Calcite, CaCO₃
Milky quartz (rough fragment)
Quartz, silicon dioxide (SiO₂)
Opalite-style pendant (likely synthetic glass, not natural opal)
Opalescent glass; commonly sold as “opalite” (not a recognized mineral species)
White pebble, likely quartz or calcite
Indeterminate from image; possible microcrystalline quartz (SiO₂) or calcite (CaCO₃)
Diamond
Native Carbon (C)
Likely clear quartz crystal or glass-like gemstone
Quartz, silicon dioxide (SiO₂); exact identification is uncertain from the strongly magenta-lit image
Aluminum Slag
Anthropogenic Aluminum (Al)
Dzi Bead (Etched Chalcedony)
Cryptocrystalline Quartz (SiO2) with chemical etching
Opalite
Synthetic glass (SiO2 + metal additions)
Opalite
Synthetic Opalised Glass
Chakra Stone Tower (Composite Multi-Mineral)
Crystalline Silicon Dioxide composite (SiO2) with various inclusions
Asphalt / Road Aggregate
Bituminous Conglomerate (synthetic)
Polymer Clay (Mock Mineral)
Polyvinyl chloride (PVC) with plasticizers and pigment
Crackled Quartz (Dyed)
Silicon Dioxide (SiO2)
Polished black stone, likely obsidian
Obsidian (volcanic glass; mostly silica-rich rhyolitic composition)
Slag
Ferrous Slag (Amorphous calcium-magnesium-aluminum silicates)
Libyan Desert Glass
Impact-melt silica glass (SiO2 + traces of Al, Fe, Ti)
Titanium-coated Metal Cube (Man-made Fidget Toy)
Titanium-anodized or electroplated alloy (e.g., Ti-coated Zinc or Aluminum)
Sea Glass (White/Clear)
Amorphous Silica (Alkali-Lime-Silica Glass), SiO2 + Na2O + CaO
Titanium Aura Quartz
Silicon Dioxide (SiO2) coated with Titanium and Niobium
Dalmatian Stone
Dalmatian Jasper (a misnomer for an Aplite with Arfvedsonite spots)
Chert (Arrowheads)
Microcrystalline Quartz (SiO2)
Titanium-Coated Hematite (Aura Hematite)
Titanium-bonded Hematite (Fe2O3 with a Ti coating)
Opalite
Synthetic Opalised Glass
Botryoidal chalcedony (likely agate/jasper variety)
Microcrystalline quartz, SiO₂