Chert (variations include Flint or Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Category
Browse sedimentary (alluvial deposit) specimens identified by the Rock Identifier community.
Chert (variations include Flint or Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Jasper/Flint Pebble)
Microcrystalline or Cryptocrystalline Silicon Dioxide (SiO2)
Wonderstone (Sandstone)
Silicified Quartz Sandstone with Iron Oxide staining
Jasper
Silicon Dioxide (SiO2) with iron oxide impurities
Puddingstone
Polymictic Conglomerate
Coquina
Coquina Limestone
Sandstone (Weathered)
Arenite (primarily SiO2)
Chert (Chalky variety)
Microcrystalline Quartz (SiO2)
Coquina Jasper
Fossiliferous Chalcedony (SiO2)
Bauxite
Bauxite (Al(OH)3, AlO(OH))
Sandstone (specifically Lithic or Quartz Arenite)
Arenite (composed primarily of SiO2)
Chert (Jasper variety)
Chert (SiO2)
Glauconitic Sandstone (Greensand pebble)
Glauconitic Quartz Sandstone (K(Fe,Al)2(Si,Al)4O10(OH)2)
Limonite (Iron-rich Siltstone / Sandstone base)
Hydrous ferric oxide mixture (FeO(OH)·nH2O)
Travertine (Ceramic Tile)
Terrestrial Sedimentary Rock / Calcium Carbonate (CaCO3)
Chert (and Chalcedony)
Microcrystalline Quartz (SiO2)
Banded Calcite (often commercially sold as 'Mexican Onyx' or 'Honey Onyx')
Calcite (Calcium Carbonate, CaCO3)
Breccia
Breccia
Sandstone (specifically Flagstone)
Arenite (primarily composed of SiO2)
Sandstone
Arenite (primarily SiO2, silica)
Sandstone with Secondary Mineral Encrustation
Arenite with Silica/Calcite deposits (SiO2 or CaCO3)
Greenschist
Chlorite schist
Sandstone (Quartzose)
Arenite (primarily SiO2)
Yellow Chalcedony (Agate Pebble)
Silicon Dioxide (SiO2)
Sandstone Concretion
Ferruginous Sandstone Concretion (Primarily SiO2 with Iron Oxide cement)
Fossiliferous Shale Matrix
Clastic Sedimentary Rock with Brachiopod or Mollusk shell fragments
Botryoidal Chalcedony with Calcite
Chalcedony (SiO2 with accessory minerals, likely CaCO3)
Sandstone (with biological crust)
Arenite (SiO2 based)
Ocherous Sandstone (Ferruginous Sandstone)
Ferruginous Arenite (SiO2 with Fe2O3)
Quartz Geode / Druzy Quartz
Silicon Dioxide (SiO2)
Pebble (likely Quartz or Chert)
SiO₂ (Silicon Dioxide) - referring to the likely main mineral composition, Quartz. If it's chert, the scientific name remains SiO₂ with a microcrystalline structure.
Green Calcite (Onyx Marble)
Calcium Carbonate (CaCO3)
Optical Calcite (Iceland Spar)
Calcite (Calcium Carbonate, CaCO3)
Chert (Flint)
Chert (microcrystalline quartz)
Carnelian Agate
Chalcedony (Silicon Dioxide, SiO2)
Celestite Geode
Celestine (Strontium Sulfate, SrSO4)
Magnetite
Magnetite (Fe3O4)
Pyrite
Iron Sulfide (FeS2)
Sandstone
Arenite (primarily SiO2 with various cementing agents)
Red Jasper
Jasper (Silicon Dioxide, SiO2 with Iron Oxide impurities)
Fossiliferous Limestone
Limestone with fossil inclusions (CaCO3)
Bauxite
Bauxite (mixture of Hydrous Aluminum Oxides)