Sandstone (with Liesegang rings or joints)
Clastic Sedimentary Rock (primarily Quartz with Iron Oxide cement)
Category
Browse man made composite (lithified equivalent of sedimentary) specimens identified by the Rock Identifier community.
Sandstone (with Liesegang rings or joints)
Clastic Sedimentary Rock (primarily Quartz with Iron Oxide cement)
Brick fragment (Man-made material)
N/A (Fired clay)
Cobalt Blue Glass / Cullet Glass
Silicon dioxide (Amorphous man-made glass)
Onyx (Black) and Mother of Pearl Inlay
Silicon Dioxide (SiO2) for Onyx; Aragonite (CaCO3) for Mother of Pearl
Unidentified translucent crystal/mineral fragment
Likely quartz (SiO₂), but visual identification is uncertain
Asphalt (Bituminous pavement)
Bituminous concrete / Asphalt
Goldstone
Man-made glass with copper inclusions
Sandstone Concretion
Septarian or Carbonate-cemented Sandstone Concretion
Sandstone Anvil / Nutting Stone
Quartzose Sandstone (Sedimentary Rock)
Porcelain Tile (Sandstone-look)
Man-made Ceramic (resembling Quartz-rich Sandstone)
Decorated turquoise-like bead or mineral pendant
Likely turquoise [CuAl₆(PO₄)₄(OH)₈·4H₂O], possibly dyed composite or blue-green jasper
Fossilized Coral (Coquina/Limestone)
Cnidaria Anthozoa (Fossilized)
Asphalt aggregate (crushed stone in bitumen)
Artificial composite; predominantly crushed granite, basalt, limestone, and/or recycled aggregate bound by bitumen
Chert (flint) fragment
Microcrystalline quartz (SiO₂), commonly called chert; “flint” is a variety of chert
Opalite
Synthetic Opalite Glass / Opalized Glass
Cullet Glass (Slag Glass)
Amorphous Silicon Dioxide (SiO2) with metallic oxide impurities
Slag (Industrial Byproduct)
Artificial silicate/iron byproduct
Titanium Coated Kyanite (Aura Kyanite)
Aluminosilicate (Al2SiO5) with a Titanium-Niobium vacuum-deposited coating
Sandstone (with concrete/human-made layer)
Clastic Sedimentary Rock (primarily Quartz/Feldspar grains)
Green Obsidian Sphere (man-made glass)
Vitreous Silica with Chromium/Iron additives
Opalite
Synthetic Opalite (Man-made glass)
Opalite
Man-made Glass (SiO2 + additives)
Transit Token (RTD Denver)
Nickel-plated brass or bronze alloy (Cu-Sn-Zn-Ni)
Goldstone
Man-made glass with copper inclusions
Blue Slag Glass
Man-made Silicon Dioxide (Amorphous)
Cullet Glass (Slag)
Amorphous Silicon Dioxide (Man-made)
Chert Concretion
Chert (Microcrystalline Quartz, SiO2)
Crescent Pebble
Weathered Quartzite or Sandstone Fragment
Boxwork or Septarian Concretion
Septarian nodule / Boxwork weathering
Diabase (Dolerite)
Diabase
Likely iron-rich slag or weathered ironstone fragment
Uncertain; possibly iron oxide–rich material (hematite/goethite) or industrial iron slag
Blue-green faceted gemstone, possibly glass or synthetic material
Not identifiable from the image; possible synthetic spinel or glass
Turquoise cabochon ring
Turquoise — hydrated copper aluminum phosphate, CuAl₆(PO₄)₄(OH)₈·4H₂O
Mystic Topaz (Treated Quartz or Topaz)
Aluminum silicate fluoride hydroxide [Al2SiO4(F,OH)2] with thin-film metallic coating
Opalite
Man-made opalescent glass (SiO2 + metal oxides)
Clear quartz fragment (rock crystal)
Quartz, silicon dioxide (SiO₂)
Faceted clear gemstone in a gold-colored setting
Unidentified transparent faceted stone; possibly quartz, glass, or another colorless gem
Concrete Rubble with Aggregate
Hardened Portland Cement Paste with Coarse Aggregate
Obsidian
Volcanic glass
Cullet Glass (Slag Glass)
Amorphous Silicon Dioxide (Industrial Man-made)
Sea Glass
Man-made vitreous material / Silicon dioxide
Baked-clay ceramic fragment (likely brick or pottery)
Fired clay, primarily aluminosilicate minerals; not a natural rock