Obsidian
Volcanic Glass (Amorphous SiO2)
Category
Browse man made byproduct (often mistaken for obsidian or emerald) specimens identified by the Rock Identifier community.
Obsidian
Volcanic Glass (Amorphous SiO2)
Ferrocoke or Slag
Anthropogenic pyrometallurgical residue
Slag (Industrial Byproduct)
Ferrous/Non-ferrous Silicate
Variscite in Matrix
Variscite (AlPO4 · 2H2O)
Obsidian
Volcanic glass (SiO2)
Iron Slag
Anthropogenic Vitreous Ferrous Silicate
Concrete rubble
Anthropogenic conglomerate
Blue Goldstone
Synthetic Avanturine Glass (or Aventurine Glass)
Opalite
Man-made opalescent glass
Iron Slag
Iron Slag (Industrial Vitreous Material)
Concrete fragment or Conglomerate
Artificial Conglomerate (Concrete) or Natural Conglomerate
Quartz pebble (Quartztite fragment)
Silicon Dioxide (SiO2)
Cullet Glass (Strawberry Glass)
Amorphous Silicon Dioxide (SiO2) with metallic dopants
Obsidian (likely black volcanic glass)
Obsidian; primarily amorphous volcanic silica glass, approximately SiO₂-rich rhyolitic composition
Efflorescence (on Clay Brick)
Crystalline salt deposits (typically Sodium Sulfate Na2SO4, Calcium Carbonate CaCO3, or Potassium Sulfate K2SO4)
Crackled Quartz (Dyed)
Silicon Dioxide (SiO2)
Terrazzo (Man-made Composite)
Cementitious or Resin-bound Lithic Composite
Ferrous Slag
Fused calcium-iron silicates (Industrial Slag)
Ferruginous Slag (Iron Smelting Byproduct)
Fused Silicate Scoria (Amorphous mixture of FeO, SiO2, and CaO)
Iron Slag
Ferrous Slag (complex silicate and oxide byproduct)
Iron Slag
Anthropogenic Iron oxide/Silicate composite
Opalite
Opalescent Glass (SiO2 + coloring agents)
Mystic Topaz (Treated Quartz or Topaz)
Aluminum silicate fluoride hydroxide [Al2SiO4(F,OH)2] with thin-film metallic coating
Slag (Industrial Glass/Metal Waste)
Artificial silicate/ferro-silicate byproduct
Titanium Aura Quartz
Titanium-coated Silicon Dioxide (SiO2)
Opalite
Synthetic Opalite (Man-made glass)
Iron Slag
Vitreous glassy waste (Fe-Si-Al-Ca compounds)
Snowflake Obsidian
Volcanic glass with Cristobalite inclusions (70–75% SiO2)
Slag
Anthropogenic Vitrophyre (Iron or Smelting Slag)
Asphalt Concrete (Bituminous Conglomerate)
Anthropogenic Bituminous Conglomerate
Asphalt (Bituminous Concrete)
Composite material (bitumen binder with mineral aggregate)
Chert (Chalky Flint Node)
Chert (Microcrystalline Quartz, SiO2)
Asphalt (Road Aggregate)
Asphalt concrete / Bituminous mixture
Tumbled black obsidian (likely)
Volcanic glass; chiefly silica-rich rhyolitic glass (SiO₂)
Silver (Jewelry form)
Native Silver (Ag)
Green Quartz / Chrysoprase / Sea Glass
Silicon Dioxide (SiO2)
Conglomerate
Conglomerate (Sedimentary rock containing rounded clasts)
Fuchsite
Chromian Muscovite (K(Al,Cr)2(AlSi3O10)(OH)2)
Chert Concretion
Chert (Microcrystalline Quartz, SiO2)
Conglomerate
Clastic Sedimentary Rock (Conglomerate)
Sandstone (with Liesegang rings or joints)
Clastic Sedimentary Rock (primarily Quartz with Iron Oxide cement)
Slag
Anthropogenic Vitreous Silicate / Ferro-silicate Slag