Obsidian Arrowhead
Volcanic Glass (Primary composition: SiO2)
igneous
Category
Igneous Or Sedimentary (Anthropogenic Modification)
Browse igneous or sedimentary (anthropogenic modification) specimens identified by the Rock Identifier community.
Learn about Igneous Or Sedimentary (Anthropogenic Modification) in the encyclopedia
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Slag
Anthropogenic Iron Silicate Glass
mineral
Leland Blue Stone
Anthropogenic Iron Smelting Slag
mineraloid
Slag Glass
Anthropogenic Amorphous Silicon Dioxide
mineral
Blue Slag Glass
Anthropogenic Amorphous Silicon Dioxide
mineral
Blue Glass or Slag Glass
Amorphous Silica (Anthropogenic Glass)
mineral
Blue Dyed Quartzite
Silicon Dioxide (SiO2) with artificial pigment
metamorphic
Asphalt Concrete
Bituminous Concrete / Asphaltic Composite
not a natural rock (man-made composite)
Concrete / Anthropogenic Conglomerate
Man-made composite material (Portland cement, aggregate, and water)
not a natural rock
Ferruginous Conglomerate (or Iron-Rich Concrete/Slag)
Clastic Sedimentary (Silicon Dioxide/Iron Oxide matrix)
sedimentary
Slag (Industrial Glass)
Anthropogenic Amorphous Vitreous Silicate
mineraloid
Green Slag Glass
Amorphous Silica Glass (Anthropogenic)
Industrial byproduct (often mistaken for obsidian or mineral)
Iron Slag
Anthropogenic Vitreous Ferrous Silicate
industrial byproduct (anthropogenic)
Blue Sea Glass
Amorphous Silica (Anthropogenic glass)
not a rock (man-made origin)
Synthetic Faux Fur Fursuit
Polyacrylonitrile / Polyester (Synthetic Textile)
not a rock (synthetic material/costume)
Quartz (possibly milky quartz)
Quartz (Silica; SiO₂)
Mineral
Small dark mineral/rock fragment
Indeterminate; possibly magnetite-bearing basalt or iron-rich slag
mineral
Metal Chain (Likely Steel or a Steel Alloy)
Steel (primarily iron and carbon); specific alloy unknown
Man-made Object (Metal/Alloy)
Gneiss and Igneous Rock Collection
Foliated Metamorphic Rock (Gneiss) / Igneous Rocks
metamorphic
Cullet Glass (Slag Glass)
Amorphous Silicon Dioxide (Industrial byproduct)
mineraloid
Sea Glass
Amorphous Silicon Dioxide (Man-made glass weathered by nature)
mineral
Green Sea Glass
Man-made vitreous material (silica glass)
gemstone
Mystic Topaz
Aluminum silicate fluoride hydroxide with titanium coating (Al2SiO4(F,OH)2)
mineral
Banded Gneiss
Gneiss (Metamorphic Rock)
metamorphic
Slag
Anthropogenic Vitreous Silica/Iron oxides
mineral-like byproduct
Synthetic Costume Accessory (Non-Geological)
Polyester and Acrylic Fiber (Anthropogenic polymer)
Synthetic / Man-made textile
Iron Slag
Anthropogenic Iron oxide/Silicate composite
Mineral-like byproduct (Technogenic)
Iron Slag
Anthropogenic Vitreous Silicate (Byproduct of Smelting)
Mineral-like byproduct
Crackled Quartz (Blue Dyed)
Silicon Dioxide (SiO2) with anthropogenic dye
mineral
Slag (Industrial By-product)
Anthropogenic Vitreous Silica/Iron Silicate
mineral
Slag
Anthropogenic Vitrification Product / Silicate Slag
Anthropogenic (Man-made industrial byproduct)
Quartz Pebble
Silicon Dioxide (SiO2)
sedimentary
Zoisite with Ruby
Anyolite (Calcium aluminum hydroxy silicate with Corundum) Ca2Al3(SiO4)3(OH)
metamorphic
Slag
Glassy silicate byproduct (anthropogenic material)
industrial byproduct
Slag
Anthropogenic Vitrophyre (Iron or Smelting Slag)
Mineral-like byproduct
Iron Slag (Industrial Byproduct)
Anthropogenic Vitrification Product/Ferrous Slag
Mineral-like Industrial Smelting Waste
Sea Glass
Amorphous Silica (Anthropogenic glass) - SiO2
mineral
Fired Clay Brick (Anthropic Rock substitute)
Anthropogenic polycrystalline ceramic (predominantly Mullite and Quartz: Al6Si2O13 + SiO2)
metamorphic (man-made / anthropic)
Common Opal
Hydrated amorphous silica (SiO2·nH2O)
mineral
Quartz on Host Rock
Silicon Dioxide (SiO2)
Mineral Specimen
Titanium Aura Quartz (Bismuth-coated Druzy)
Silicon Dioxide (SiO2) with Titanium/Metal vapor coating
mineral
Gneiss
Gneiss (High-grade metamorphic rock)
metamorphic