Dark gray rounded stone, possibly basalt or slag
Uncertain; likely fine-grained basalt (plagioclase–pyroxene) or iron-rich industrial slag
Category
Browse anthropogenic (man made industrial byproduct) specimens identified by the Rock Identifier community.
Dark gray rounded stone, possibly basalt or slag
Uncertain; likely fine-grained basalt (plagioclase–pyroxene) or iron-rich industrial slag
Sea Glass (Frosted Glass)
Amorphous Silica (SiO2) with various additives
Sea Glass (Uranium/Vaseline Glass variant)
Silicon Dioxide (SiO2) with trace Uranium Oxide (U3O8)
Diamond
Carbon (C)
Rough Diamond
Pure Carbon (C)
Chert (Chalcedony/Agate variety)
Silicon Dioxide (SiO2)
Diamond
Diamond (pure Carbon, C)
Chert / Jasper
Silicon Dioxide (SiO₂)
Sea Glass (Kelly Green)
Amorphous Silica (Silicon Dioxide with Iron/Chromium additives)
Diamond
Diamond (pure carbon C)
Diamond
Native Carbon (C)
Note: Item is not a geological specimen
Polyester mesh and Ethylene-vinyl acetate (EVA) polymer
Sandstone
Arenite (SiO2 based clastic rock)
Diamond (as featured in jewelry)
Diamond (C - pure carbon)
Sandstone (Ferruginous)
Arenite (SiO2 with Fe2O3 inclusions)
Diamond
C (Carbon)
Tumbled chalcedony (likely moss or dendritic agate)
Microcrystalline quartz, SiO₂, with iron-oxide inclusions
Probable amber fragment
Amber (fossilized plant resin; chiefly amorphous organic resin, commonly dominated by succinite)
Terrazzo (with Marble and Granite fragments)
Cementitious or resinous composite containing Calcium Carbonate (CaCO3) and Silicates
Diamond
Carbon (C)
Rough Diamond
Diamond (pure Carbon, C)
Diamond
Cubic carbon (C)
Corundum (Sapphire variant)
Aluminium oxide (Al2O3)
Basalt
Basalt
Tumbled greenstone (likely serpentinite or green jasper)
Serpentinite, commonly dominated by serpentine-group minerals (Mg₃Si₂O₅(OH)₄); exact identification requires testing
Chert (Yellow Jasper/Flint pebble)
Microcrystalline Quartz (SiO2)
Likely iron-rich rock or weathered metallic mineral fragment
Uncertain; possibly limonite/goethite or iron-bearing slag
Diamond
Carbon (C)
Diamond
Native Carbon (C)
White Marble
Recrystallized Calcite (CaCO3)
Diamond (in jewelry setting)
Carbon (C)
Diamond ring
Diamond, crystalline carbon (C)
Diamond
C (Pure Carbon)
Granite (Pegmatitic)
Phaneritic Felsic Igneous Rock
Diamond
Carbon (C)
Chert (and Jasper/Chalcedony mixture)
Microcrystalline Quartz (SiO2)
Fossilized oyster shell
Bivalvia; likely an oyster (Ostreidae), partly mineralized with calcite
Diamond (in jewelry setting)
Adamantine Carbon (C)
Diamond
Diamond (Pure Carbon, C)
Diamond (Cluster Ring)
Carbon (C)
Synthetic Blue Aura Quartz
Silicon Dioxide (SiO2) with Metallic Infusion
Man-made Green Quartz (Lab-grown or Treated)
Silicon Dioxide (SiO2) with artificial coloration