Fired Clay Brick (Anthropic Rock substitute)
Anthropogenic polycrystalline ceramic (predominantly Mullite and Quartz: Al6Si2O13 + SiO2)
metamorphic (man-made / anthropic)
Category
Mineral (Man Modified)
Browse mineral (man modified) specimens identified by the Rock Identifier community.
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Cullet Glass (Strawberry Glass)
Amorphous Silicon Dioxide (SiO2) with metallic dopants
Mineraloid (Synthetic/Man-made)
Asphalt Concrete
Bituminous Concrete / Asphaltic Composite
not a natural rock (man-made composite)
Chipped Glass/Plastic Fragment
Silicon dioxide (SiO2) for glass (amorphous) or various polymer compounds for plastic
Man-made material (simulant/artifact)
Blue Slag Glass
Amorphous Silica (Industrial byproduct)
Antropogenic (Man-made glass byproduct)
Green Glass Cullet / Recycled Glass
Amorphous Silicon Dioxide (SiO2) with various metal oxides
Man-made Glass (Not a natural rock or mineral)
Ferrosilicon Slag (Industrial Vitrified Glass)
Vitreous Silicate Residue
Antropogenic (Man-made industrial byproduct)
United States Quarter Dollar
Cupronickel Clad Alloy (75% Copper, 25% Nickel over a 100% Copper core)
Metal / Man-made mineral-like object
Metallic Ornament / Jewelry
N/A - This is an artificial object, not a geological specimen.
This appears to be a man-made metallic object, likely jewelry, not a natural rock, mineral, or geological specimen.
Green Slag Glass
Cullet (Amorphous Silicon Dioxide with impurities)
Man-made rock-like material
Slag Glass (Cullet)
Amorphous Silica / Glass residue
Man-made byproduct (Non-geological)
Asphalt (Bituminous Concrete)
Bituminous mix / Anthropogenic conglomerate
man-made composite (lithified equivalent of sedimentary)
US Penny
Cuprum (Copper: Cu) and Zincum (Zinc: Zn) Alloy
Man-made object (metal alloy)
Synthetic Blue Aura Quartz
Silicon Dioxide (SiO2) with Metallic Infusion
mineral (synthetic/man-made coating)
Smoky quartz crystal cluster
Quartz, silicon dioxide (SiO₂), likely smoky variety
mineral
Sea Glass (Teal/Turquoise)
Amorphous Silica (SiO2) with trace metal oxides
Anthropogenic (Man-made material processed by nature)
Cullet Glass (Industrial Slag Glass)
Amorphous Silica (SiO2) with metallic oxide impurities
Man-made byproduct (often mistaken for Obsidian or Emerald)
Sodalite
Sodalite (Sodium Aluminum Silicate Chloride), Na8(Al6Si6O24)Cl2
Mineral
Chert (Arrowhead or Projectile Point)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Sodalite
Sodalite - Na8(Al6Si6O24)Cl2
Mineral
Painted pebble, likely a smooth river stone
Unidentified fine-grained natural rock; exact lithology cannot be determined from the image
sedimentary
Nutting Stone / Cupstone (Sandstone or Quartzite)
Sedimentary rock with anthropogenic modification (cupule)
sedimentary
Blue beach pebble, likely milky quartz or quartz-rich stone
Quartz (SiO₂), possibly a quartz-rich pebble; identification is tentative from the image
mineral
Weathered granite
Granite, a coarse-grained felsic intrusive igneous rock
igneous
Polished stone sphere, possibly agate or jasper
Likely microcrystalline quartz (SiO₂); exact variety cannot be confirmed from the image
mineral
Chert Arrowhead
Microcrystalline Quartz (SiO2)
sedimentary
Schist
Schist (Crystalline metamorphic rock)
metamorphic
Likely weathered native copper-bearing rock
Unidentified copper-bearing specimen; native copper (Cu) is possible but cannot be confirmed visually
mineral
Limestone with Calcite Veins
Calcium Carbonate (CaCO3)
sedimentary
Blue druzy quartz cluster
Quartz, SiO₂; blue coloration likely from inclusions or surface treatment
mineral
Likely fluorite crystal fragment
Fluorite (calcium fluoride, CaF₂)
mineral
Tumbled dark green stone, likely serpentinite or greenstone
Serpentinite (antigorite/lizardite-rich), or chlorite–amphibole greenstone
metamorphic
Tumbled serpentine or soapstone pebble
Serpentine-group minerals, chiefly antigorite/lizardite; possibly talc-rich steatite
metamorphic
Granodiorite
Granodiorite
Igneous
Quartzite Arrowhead (Archaeological Lithic)
Recrystallized Quartz (SiO2)
metamorphic
Likely garnet-bearing rock
Garnet in a dark metamorphic matrix; garnet is commonly almandine, Fe₃Al₂(SiO₄)₃
metamorphic
Likely dark green jasper or serpentinite pebble
Undetermined fine-grained rock; possible serpentine-group mineral (approx. Mg₃Si₂O₅(OH)₄) or jasper (microcrystalline SiO₂)
metamorphic
Iron-oxide-stained rock with a pale mineral vein
Likely limonite/goethite-stained quartz-bearing rock; exact identification is uncertain from the image
sedimentary
Chert (Yellow or Tan Chert)
Silicon Dioxide (SiO2)
sedimentary
Iron-rich rock, possibly limonite/goethite-bearing quartz or weathered ironstone
Limonite (FeO(OH)·nH₂O), commonly mixed with goethite (α-FeO(OH)) and quartz
mineral
Raw green calcite (probable)
Calcite, CaCO₃; green coloration may reflect inclusions or alteration minerals
mineral
Polished red jasper
Jasper, an opaque microcrystalline variety of quartz (SiO₂), colored mainly by iron oxides
mineral