Chert Arrowhead
Microcrystalline Quartz (SiO2)
Category
Browse industrial byproduct (anthropogenic material) specimens identified by the Rock Identifier community.
Chert Arrowhead
Microcrystalline Quartz (SiO2)
Mystic Topaz
Aluminum silicate fluoride hydroxide with titanium coating (Al2SiO4(F,OH)2)
Orange Calcite
Calcium Carbonate (CaCO3)
Bituminous Coal
Coal (Organically derived sedimentary rock)
Chert (Arrowheads)
Microcrystalline Quartz (SiO2)
Green Slag Glass
Amorphous Silica / Glassy Blast Furnace Slag
Possible tektite or volcanic glass specimen
Natural silica glass; composition commonly near SiO₂, but exact identification requires chemical testing
Chert (Jasper)
Microcrystalline Quartz (SiO2)
Green Sea Glass
Man-made vitreous material (silica glass)
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
Chert Arrowhead (Projectile Point)
Microcrystalline Quartz (Chert or Flint)
Quartz (Engineered Quartz Surface)
Silicon Dioxide (SiO2) based composite
Slag (Industrial Glass/Metal Waste)
Artificial silicate/ferro-silicate byproduct
Slag
Cullet Glass (sometimes mistaken for Blue Obsidian or Slag)
Amorphous Silicon Dioxide (SiO2) with chemical additives (e.g., Cobalt for blue color)
Jasper (Multi-colored) / Sea Glass Slag
Silicon Dioxide (SiO2) with impurities of Iron Oxide
Sandstone (likely Fossilized Wood or Concrete Simulacrum)
Arenite / Silicified Wood / Anthropogenic Concrete
Chert (Arrowhead/Projectile Point)
Cryptocrystalline Quartz (SiO2)
Sandstone-based Concrete Fragment
Cementitious Composite with Sedimentary Aggregate
Chert (Arrowhead Fragment)
Microcrystalline Quartz (SiO2)
Asphalt (Bituminous Concrete)
Bituminous mix containing aggregates and petroleum-based binder (CnH2n+2)
Note: Item is not a geological specimen
Polyester mesh and Ethylene-vinyl acetate (EVA) polymer
Red Slag Glass
Amorphous Silica (Industrial byproduct with metallic oxide dopants)
Chert (Arrowhead/Tool variety)
Microcrystalline Quartz (SiO2)
Painted River Rock
Artificially Coated Sedimentary Rock
Concrete
Anthropogenic Sedimentary Rock (Hydrated Calcium Silicate)
Quartz (Milky/River Quartz)
Silicon Dioxide (SiO2)
Asphalt (Road Aggregate)
Bituminous Conglomerate / Asphalt Concrete
Eroded Brick or Pumice-like Scoria
Vesicular Basalt / Scoria (Anthropogenic variant: Eroded Firebrick)
Mother of Pearl (Nacre)
Aragonite (CaCO3) with Organic Matrix
Chert / Flint Handaxe
Cryptocrystalline Quartz (SiO2)
Painted River Pebble (likely Basalt or Greywacke)
Aphanitic Lithic Clast with Anthropogenic Pigment coating
Quartzite Arrowhead (Archaeological Lithic)
Recrystallized Quartz (SiO2)
Chert (Arrowhead Preform or Point)
Chert (Microcrystalline Quartz, SiO2)
Green Obsidian Sphere (man-made glass)
Vitreous Silica with Chromium/Iron additives
Likely slag or metallic industrial byproduct
Unidentified iron-rich ferrous slag; possibly magnetite-bearing slag
Pyrite in Matrix
Iron Sulfide (FeS2)
Concrete Fragment
Hardened Portland cement and mineral aggregate
Fired Clay Brick (Anthropic Rock substitute)
Anthropogenic polycrystalline ceramic (predominantly Mullite and Quartz: Al6Si2O13 + SiO2)
Chert (Arrowhead Fragment)
Silicon Dioxide (SiO2)
Tiffany Stone
Bertrandite-Bearing Fluorite Hyalite Opal
Chert Arrowhead
Cryptocrystalline Quartz (SiO2)