Exposed Aggregate Concrete (Pea Gravel)
Concrete with Siliceous Alluvial Gravels
Category
Browse synthetic glass (man made) specimens identified by the Rock Identifier community.
Exposed Aggregate Concrete (Pea Gravel)
Concrete with Siliceous Alluvial Gravels
Chert (Arrowheads)
Microcrystalline Quartz (SiO2)
Sea Glass
Man-made silicate glass weathering product
Blue opalite (often sold as synthetic opal)
Opalite glass; amorphous hydrated silica if natural opal (SiO₂·nH₂O)
Concrete Fragment
Hardened Portland cement and mineral aggregate
Cullet Glass (sometimes mistaken for Blue Obsidian or Slag)
Amorphous Silicon Dioxide (SiO2) with chemical additives (e.g., Cobalt for blue color)
Green Aventurine
Quartzite with Fuchsite inclusions (SiO2 + K(Al,Cr)2(AlSi3O10)(OH)2)
Synthetic Costume Accessory (Non-Geological)
Polyester and Acrylic Fiber (Anthropogenic polymer)
Green glass sphere/marble
Soda-lime glass (primarily SiO2, Na2O, CaO)
Orgonite Pyramid (containing Amethyst and mixed minerals)
Silicon Dioxide (SiO2) in synthetic resin
Goldstone
Aventurine Glass (Man-made glass with copper inclusions)
Asphalt Concrete
Bituminous conglomerate
Slag (Industrial Byproduct)
Artificial silicate/iron byproduct
Blue Goldstone
Man-made glass with suspended copper, cobalt, or manganese particles
Mystic Topaz (Treated Quartz or Topaz)
Aluminum silicate fluoride hydroxide [Al2SiO4(F,OH)2] with thin-film metallic coating
Sandstone Concretion
Limonitic Sandstone Concretion
Cobalt Glass Slug (Cullet)
Man-made Silicate Glass with Cobalt Oxide (CoO)
Ferrous Slag
Iron/Steel Slag (Complex Calcium-Alumino-Silicates)
Aura Quartz (Rainbow Quartz)
Silicon Dioxide (SiO2) with metallic vapor coatings
Asphalt (Road Aggregate)
Bituminous conglomerate
Pyrite in Quartz (Drill Core)
Silicon Dioxide (SiO2) with Iron Sulfide (FeS2) inclusions
Blue Goldstone
Goldstone (artificial glass)
Jewelry Chain with Blue and Clear Gemstones (Likely Cubic Zirconia)
Cubic Zirconia (ZrO₂), Silver or White Gold/Platinum Alloy
Pearls (likely freshwater cultured pearls)
Pearl: nacre, primarily aragonite (CaCO₃) with conchiolin
Strawberry Quartz
Silicon Dioxide (SiO2) with Hematite/Goethite inclusions
Goldstone (Brown/Gold)
Aventurine Glass (Man-made glass with Copper inclusions)
Transit Token (RTD Denver)
Nickel-plated brass or bronze alloy (Cu-Sn-Zn-Ni)
Goldstone (Red)
Aventurine Glass
Concrete Rubble with Aggregate
Hardened Portland Cement Paste with Coarse Aggregate
Concrete
Anthropogenic Conglomerate
Concrete with Aggregate
Composite construction material; primary matrix is Calcium Silicate Hydrate (C-S-H)
Chert Concretion
Chert (Microcrystalline Quartz, SiO2)
Unidentifiable Rock Fragment
Asphalt Concrete (Bituminous Conglomerate)
Anthropogenic Bituminous Conglomerate
Cullet (Slag Glass)
Amorphous Silica (Industrial byproduct)
Citrine Quartz
Citrine (Silicon Dioxide, SiO2)
Crushed Stone (Likely Limestone or Granite)
Calcium Carbonate (CaCO3) for Limestone / Quartz and Feldspar for Granite
Chert Arrowhead (Projectile Point)
Microcrystalline Quartz (Chert or Flint)
Aura Quartz (Titanium Quartz)
Titanium-coated Silicon Dioxide (SiO2 + Ti)
Concretion (Sandstone)
Carbonate-cemented Sandstone Concretion
Blue-beaded gemstone jewelry, likely lapis lazuli or dyed blue agate
Uncertain from the image; possible lazurite-bearing lapis lazuli (Na₃Ca(Si₃Al₃)O₁₂S) or blue chalcedony (SiO₂)
Aggregate Concrete
Anthropogenic Conglomerate (Technosol)