Basaltic Tuff / Volcanic Breccia
Pyroclastic Breccia / Lithic Tuff
igneous
Category
Mineral Based Alloy (Anthropogenic)
Browse mineral based alloy (anthropogenic) specimens identified by the Rock Identifier community.
Learn about Mineral Based Alloy (Anthropogenic) in the encyclopedia
View all →
Concrete fragment or Conglomerate
Artificial Conglomerate (Concrete) or Natural Conglomerate
sedimentary
Limestone (River or Sea Cobble)
Calcium Carbonate (CaCO3)
sedimentary
Sandstone Clast
Arenite (primarily SiO2)
sedimentary
Metallic meteorite fragment (probable stony-iron or iron meteorite)
Undetermined meteoritic Fe–Ni alloy with silicate minerals
meteorite
Brown Chert
Cryptocrystalline Silica (SiO2)
sedimentary
Sandstone Cobble
Arenite (Secondary classification based on grain size)
sedimentary
Bumble Bee Jasper
Calcite-bearing Volcanic Tuff (not a true Jasper)
sedimentary
Iron Meteorite
Iron-Nickel Alloy (Kamacite and Taenite)
meteorite
Iron Meteorite (Oxidized)
Iron-Nickel Alloy (Fe, Ni)
meteorite
Marble
Metamorphic rock composed of Recrystallized Carbonate Minerals (chiefly CaCO3)
metamorphic
Citrine
Citrine (Silicon Dioxide - SiO2)
mineral
Ferro-Manganese Slag
Vitreous Silicate Slag
Anthropogenic (Industrial byproduct)
Blue Kyanite in Schist
Al2SiO5 in Mica Schist
metamorphic
Puddingstone
Conglomerate
sedimentary
Crinoid Stem Fossil
Crinoidea (Class)
fossil
Dark metamorphic rock, likely slate or phyllite
Foliated metapelite; commonly mica-rich quartz–clay mineral assemblage
metamorphic
Red glassy cabochon, likely synthetic ruby or red glass
Uncertain; possible synthetic corundum (Al₂O₃, chromium-colored) or man-made glass
gemstone
Likely blue glass or synthetic gemstone jewelry
Uncertain; possibly synthetic spinel, cubic zirconia, or blue glass
gemstone
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
sedimentary
Quartzite river stone
Quartzite (SiO2)
metamorphic
Fossilized Shark Tooth
Chondrichthyes (Class)
fossil
Sandstone (likely Graywacke or Lithic Sandstone)
Arenite / Wacke (SiO2 based with lithic fragments)
sedimentary
Blue-green turquoise (probable)
Turquoise, hydrous copper aluminum phosphate — CuAl₆(PO₄)₄(OH)₈·4H₂O
mineral
Micro-Meteorite (Micrometeoroid)
Extraterrestrial Spherule (Silicate or Iron-Nickel)
mineral
Jasper
Jasper (Silicon Dioxide, SiO2)
sedimentary
![Sodium Polyacrylate (Superabsorbent Polymer) (Sodium Polyacrylate [-CH2-CH(COONa)-]n) — mineral (synthetic)](https://media.rockidentification.com/826c0c25-9fc0-4529-9425-5fa125f2a82f-thumbnail.jpg)
Sodium Polyacrylate (Superabsorbent Polymer)
Sodium Polyacrylate [-CH2-CH(COONa)-]n
mineral (synthetic)
Sandstone (Ferruginous)
Arenite with Iron oxide staining (SiO2 with Fe2O3)
sedimentary
Aquamarine (Small Beads)
Beryl (Be3Al2Si6O18 with traces of iron)
gemstone
Gold Nugget
Native Gold (Au)
mineral
Amethyst Geode
Amethyst (Silicon Dioxide), Formula: SiO2
mineral
Likely metallic mineral specimen
Probably galena (lead sulfide, PbS), though visual identification is uncertain
mineral
Gold Nugget
Native Gold (Au)
mineral
Amethyst Geode
Silicon Dioxide (SiO2) with iron impurities
mineral
Faceted Peach Morganite (Beryl)
Morganite (Be3Al2Si6O18 with trace Manganese)
mineral
Gold Nugget
Native Gold (Au)
mineral
Chert (Jasper)
Microcrystalline Quartz (SiO2)
sedimentary
Riverstone Quartzite / Chalcedony Nugget
Silicon Dioxide (SiO2)
metamorphic
Metal Chain Belt with Square Plates
Not applicable (man-made)
Man-made Object (Metalwork)
Amethyst Sage Agate
Silicon Dioxide (SiO2) with trace minerals (Manganese/Iron oxides)
mineral
Iron Slag
Ferrous Slag (complex silicate and oxide byproduct)
industrial byproduct (anthropogenic)
Diamond Drill Core (Greenschist and Quartzite)
Chlorite Schist / Meta-quartzite (Metamorphic Rock Core Sample)
metamorphic