Chert (Jasper/Chalcedony)
Microcrystalline Silica (SiO2)
Category
Browse sedimentary rock (technically a variety of chalcedony) specimens identified by the Rock Identifier community.
Chert (Jasper/Chalcedony)
Microcrystalline Silica (SiO2)
Onyx (Black Onyx)
Onyx (Silicon Dioxide, SiO2)
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Fe2O3 staining)
Blue Calcite
Calcium Carbonate (CaCO3)
Banded Chert
Microcrystalline Quartz (SiO2)
Fuchsite Schist
Chromium-rich Muscovite (K(Al,Cr)2(AlSi3O10)(OH)2) in Schist
Sandstone
Arenite
Sandstone (Quartzose Sandstone)
Arenite (primarily SiO2)
Ferruginous Quartz
Silicon Dioxide (SiO2) with Iron Oxide inclusions (Hematite/Goethite)
Banded Chert
Silicon Dioxide (SiO2)
Sandstone
Arenite
Sandstone
Arenite (Sedimentary rock composed of sand-sized grains, primarily SiO2)
Quartz (specifically Milky/White Quartz)
Silicon Dioxide (SiO2)
Yellow Calcite
Calcium Carbonate (CaCO3)
Fluorite
Fluorite (Calcium Fluoride, CaF2)
Sandstone
Arenite
Pebble (Likely Basalt or Siltstone)
Clastic sedimentary rock or mafic volcanic rock
Milky Quartz
Silicon Dioxide (SiO2)
Marble
Marble (metamorphosed limestone/dolostone). Predominantly composed of Calcite (CaCO3) for marble derived from limestone, or Dolomite (CaMg(CO3)2) for marble derived from dolostone.
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Blue Apatite
Apatite group (Ca5(PO4)3(F,Cl,OH))
Quartz Geode
Silicon Dioxide (SiO2)
Chert (Jasper variety)
Silicon Dioxide (SiO2)
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Gneiss
High-grade metamorphic rock (Gneiss)
Milky Quartz with Iron Inclusions
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Sandstone Cobble
Clastic Sedimentary (Sandstone)
Chalcedony (specifically Agate or Flint)
Silicon Dioxide (SiO₂)
Chert (Jasper/Mudstone variant)
Silicon Dioxide (SiO2)
Painted River Rock
Anthropogenic-modified Siliciclastic Sedimentary Rock
Sandstone
Arenite (primarily SiO2)
Shale
Shale (composition varies: primarily clay minerals and quartz)
Sandstone (Ferruginous)
Arenite with Iron Oxide staining (Fe2O3)
Sandstone
Arenite (SiO2 based)
Sandstone
Arenite
Garnet (Red Garnet)
Garnet Group. The red varieties seen in jewelry are typically Almandine (Fe3Al2(SiO4)3), Pyrope (Mg3Al2(SiO4)3), or a mix of the two (pyrope-almandine series).
Potassium Feldspar
Orthoclase (KAlSi3O8)
Peridot
Olivine ((Mg, Fe)2SiO4)
Quartz (Druzy or Crystalline variety)
Silicon Dioxide (SiO2)
Garnet (Almandine)
Almandine (Fe3Al2(SiO4)3)
Gneiss
High-grade regional metamorphic rock (Foliated)