Sandstone
Arenite (primarily SiO2)
Category
Browse mineraloid like synthetic material specimens identified by the Rock Identifier community.
Sandstone
Arenite (primarily SiO2)
Limestone
Limestone (Calcium Carbonate, CaCO3)
Yellow Quartzite
Quartzite (SiO2 with iron oxide impurities)
Chert (Flint)
Silicon Dioxide (SiO2)
Chert (and Jasper variety)
Microcrystalline Quartz (SiO2)
Quartz (Iron-stained)
Silicon Dioxide (SiO2)
Fossilized oyster or bivalve shell
Fossil Gryphaeidae or Ostreoidea; calcitic shell, CaCO₃
Sandstone
Sedimentary Rock (Quartz arenite / Lithic sandstone)
Scoria (Lava Rock)
Scoria (basaltic pyroclastic rock)
Sandstone (Quartz Arenite)
Sandstone (Chemical formula: primarily SiO2)
Sandstone (Wonderstone)
Arenite (composed primarily of SiO2 with Fe2O3 impurities)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Sandstone (Ferruginous)
Arenite (SiO2 with iron oxide impurities)
Sandstone
Arenite
Sandstone (River Rock)
Arenite (SiO2 based sedimentary rock)
Quartzite with inclusions
Quartzite (SiO2)
Chert (Flint)
Chert (Cryptocrystalline Silica/SiO2)
Chert (Jasper/Agate variety)
Microcrystalline quartz (SiO2)
Iron Meteorite
Siderite (Iron-Nickel Meteorite)
Sandstone
Arenite (Sedimentary rock)
Sandstone
Arenite
Red Sandstone
Arenite (Ferruginous Sandstone)
Bauxite
Bauxite (mixture of Gibbiste Al(OH)3, Boehmite ̳-AlO(OH), and Diaspore ́-AlO(OH))
Microcrystalline Quartz (Chert/Agate)
Silicon Dioxide (SiO2)
Carnelian / Chalcedony
Silicon Dioxide (SiO2)
Coquina
Biogenic Limestone (Calcite / CaCO3)
Fossilized coral or porous marine limestone
Likely fossil coral (Scleractinia), composed mainly of calcite/aragonite (CaCO₃)
Biotite (Black Mica)
Biotite (K(Mg,Fe)3AlSi3O10(OH)2)
Chalcedony (Agate / Jasper Specimen)
Silicon Dioxide (SiO2)
Muscovite Mica
KAl2(AlSi3O10)(OH)2
Siltstone or Mudstone
Siltstone (composed primarily of silt-sized particles)
Likely petrified wood or silicified fossil fragment
Silicified wood; predominantly microcrystalline quartz (SiO₂)
Sandstone
Arenite (variable SiO2 composition)
Chert (specifically Flint or Chalcedony nodule)
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (Permineralized Lycopsid, Conifer, or Hardwood)
Quartz Crystal Fragment
Silicon Dioxide (SiO2)
Sandstone
Sedimentary Clastic Rock (Quartz Arenite)
Brown Agate
Cryptocrystalline Quartz (SiO2)
Tumbled dark green stone, likely serpentine
Serpentinite; chiefly serpentine-group minerals (Mg₃Si₂O₅(OH)₄)
Siltstone
Siltstone (primarily SiO2, Al2O3)
Chert (Flint)
Silicon Dioxide (SiO2)
Chert with Iron Staining
Microcrystalline Quartz (SiO2)