Chert (varietal: Flint or River Pebble)
Silicon Dioxide (SiO₂)
Category
Browse sedimentary (alluvial deposit) specimens identified by the Rock Identifier community.
Chert (varietal: Flint or River Pebble)
Silicon Dioxide (SiO₂)
Chert (Jasper/Flint variant)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Coquina / Shelly Limestone
Bioclastic Limestone (composed of CaCO3)
Chalk
Calcium Carbonate (CaCO3)
Sandstone with Manganese Dendrites/Oxide coatings
Arenite with Pyrolusite and Romanechite (MnO2)
Gneiss (Metamorphic Rock)
Gneiss (high-grade regional metamorphic rock)
Chert (Limestone-based)
Silicon Dioxide (SiO2)
Limestone
Calcium Carbonate (CaCO3)
River Siltstone Pebble
Siltstone (primarily composed of silica and clay minerals)
Jasper
Silicon Dioxide (SiO2) with impurities (mostly Iron Oxides)
Sandstone (Quartz-rich Pebble)
Arenite (primarily SiO2)
Red Sandstone
Arenite (primarily Quartz SiO2 with Hematite Fe2O3 cement)
Chert (Black Chert/Flint)
Silicon Dioxide (SiO2)
Jasper (Iron-stained Chert)
Silicon Dioxide (SiO2)
Banded Chert
Microcrystalline Quartz (SiO2)
Jasper with Quartz Veining
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Chalk
Micrite (primarily Calcium Carbonate, CaCO3)
Chalcedony (Grey/White Agate)
Silicon Dioxide (SiO₂)
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Pyrite
Iron Sulfide (FeS2)
Common Opal (Green Opal / Pistachio Opal)
Hydrated silica (SiO2·nH2O)
Anthracite Coal
Anthracite (Carbon-rich metamorphic rock)
Aventurine (Green)
Silicon Dioxide (Quartz) with inclusions typically of Fuchsite; SiO2
Raw Emerald
Beryl (Be3Al2(SiO3)6) with Cr/V impurities
White Quartz (Milky Quartz)
Quartz (Silicon Dioxide, SiO2)
Amber Inlay Jewelry
Fossilized Resin (C10H16O)
Rhodochrosite
Manganese Carbonate (MnCO3)
Sandstone (likely Arkosic or Lithic)
Clastic Sedimentary Rock (SiO2 with accessory minerals)
Sandstone (with potential Quartzite characteristics)
Clastic sedimentary rock (primarily SiO2)
Sandstone
Arenite (primarily SiO2)
Fossiliferous Limestone with Rugose Coral
Calcium Carbonate (CaCO3) featuring Rugosa (extinct order of solitary and colony corals)
Sandstone (likely Fossiliferous)
Arenite / Sedimentum arenaceum
Jasper (Red Jasper with Quartz veins)
Jasper (Silicon Dioxide, SiO2)
Chert (Jasper/Flint variety)
Microcrystalline silicon dioxide (SiO2)
Ocean Jasper
Silicon dioxide with impurities (SiO2 + impurities)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Hematite
Iron(III) oxide (Fe2O3)
Red Jasper
Silicon Dioxide (SiO2) with Hematite inclusions
Red Jasper
Silicon Dioxide (SiO2) with Iron Oxide inclusions
Carnelian
Carnelian (SiO2 - Silicon Dioxide with Iron Oxide impurities)
Sandstone with Magnetite and Iron Staining
Clastic Sedimentary Rock (contains Fe3O4 and Limonite/Hematite)
Coquina
Bioclastic Limestone (composed primarily of CaCO3)