Botryoidal chalcedony with iron-oxide staining
Microcrystalline quartz (SiO₂), likely iron-oxide-bearing chalcedony
Category
Browse anthropogenic (man made industrial byproduct) specimens identified by the Rock Identifier community.
Botryoidal chalcedony with iron-oxide staining
Microcrystalline quartz (SiO₂), likely iron-oxide-bearing chalcedony
Dark quartz point (possibly smoky quartz)
Quartz, SiO₂; the dark color may indicate smoky quartz, but the image is insufficient to confirm
Polished orbicular jasper (likely ocean jasper)
Siliceous microcrystalline quartz/chalcedony with iron-oxide and volcanic inclusions; commonly called ocean jasper
Diamond (in Jewelry)
Carbon (C)
Goldstone (blue/black aventurine glass)
Man-made aventurine glass; silica glass containing metallic copper or other glittering inclusions
Small clear crystal, possibly quartz or glass-like gemstone
Uncertain; likely quartz (SiO₂), but the image is insufficient to exclude man-made glass or cubic zirconia
Diamond
Carbon (C)
Yellow cabochon gemstone, likely citrine or yellow glass imitation
Quartz (SiO₂), if natural citrine; visual evidence is insufficient to exclude man-made glass or resin
Polished green-and-black banded cabochon (likely malachite imitation or dyed agate)
Uncertain; possible malachite (Cu₂CO₃(OH)₂), banded agate (SiO₂), or man-made glass
Green glass cabochon or tumbled stone
Indeterminate; likely man-made glass, possibly aventurine glass rather than a natural mineral
Blue goldstone beads
Man-made aventurine glass (silica glass with metallic copper inclusions), not natural lapis lazuli
Likely tumbled epidote-bearing rock or green jasper
Epidote-group silicate, possibly in a jasper or serpentinite matrix
Diamond (Cut jewelry specimen)
Diamond (pure Carbon, C)
Synthetic Costume Glove (Paws)
Polyethylene terephthalate (Polyester) & Polyurethane blend
Blue glass-like tumbled specimen
Most likely cobalt-blue slag glass or manufactured glass; not confidently identifiable as a natural mineral from the image
Dark rounded pebble, likely basalt or slag
Probable fine-grained mafic rock; possibly basalt (plagioclase–pyroxene) or industrial iron/steel slag
Colorless faceted gemstone, likely glass or cubic zirconia
Uncertain; possible cubic zirconia (ZrO₂) or quartz (SiO₂), but the image may show a man-made simulant
Colorless faceted quartz-like gemstone
Likely quartz (SiO₂), though the appearance may also indicate man-made glass or cubic zirconia
Coal (Bituminous Coal)
Caustobiolith / Sedimentary Rock
Diamond (or Diamond Simulant)
Carbon (C)
Red Sandstone
Arenite (Ferruginous Sandstone)
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)
Diamond
Carbon (C)
Flaked stone projectile point
Likely worked chert or fine-grained silicified shale; exact lithology cannot be confirmed from the image
Sea Glass (Kelly Green)
Amorphous Silica (Silicon Dioxide with Iron/Chromium additives)
Jasper / Chert (Red)
Cryptocrystalline quartz (SiO2)
Limestone
Sedimentary Rock (Primarily CaCO3)
Diamond in Kimberlite
Diamond in Kimberlite Matrix (Diamond: C, Kimberlite: complex Potassic Peridotite)
Weathered fossil shell fragment
Indeterminate bioclastic carbonate, likely molluscan shell (calcium carbonate, commonly aragonite or calcite)
Tumbled epidote-bearing rock (likely epidote–quartz–feldspar aggregate)
Epidote-rich metamorphic rock; minerals likely epidote (Ca₂(Al,Fe)₃Si₃O₁₂(OH), quartz, feldspar, and dark amphibole/biotite)
Diamond
Carbon (C)
Terrazzo (with Marble and Granite fragments)
Cementitious or resinous composite containing Calcium Carbonate (CaCO3) and Silicates
Diamond
Diamond (pure Carbon, C)
Possible basalt or iron-rich slag
Basalt (tentative; identification uncertain from image)
Small dark rock fragment
Uncertain; possibly weathered basalt or slag
Diamond
Diamond (pure carbon C)
Diamond
Carbon (C)
Dark gray rounded stone, possibly basalt or slag
Uncertain; likely fine-grained basalt (plagioclase–pyroxene) or iron-rich industrial slag
Diamond
Native Carbon (C)
Diamond (as featured in jewelry)
Diamond (C - pure carbon)