Fluorite
Calcium Fluoride (CaF2)
Category
Browse sedimentary (silicified fossiliferous chalcedony) specimens identified by the Rock Identifier community.
Fluorite
Calcium Fluoride (CaF2)
Marble
Recrystallized Calcite (CaCO3)
Quartz (Milky/Crystalline variety)
Silicon Dioxide (SiO2)
Quartz Mineral
Silicon Dioxide (SiO2)
Pyrite
Iron Sulfide (FeS2)
Ruby in Kyanite
Corundum in Disthene (Al2SiO5 + Al2O3)
Quartz (likely Herkimer Diamond style)
Silicon Dioxide (SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)
Chert (Red Jasper variety)
Silicon Dioxide (SiO2)
Limonite (Iron Ore)
Limonite (FeO(OH)·nH2O)
Limonite (Iron Ore)
FeO(OH)·nH2O (Hydrous ferric oxide)
Pyrite in Matrix (often with Chalcopyrite)
Iron Sulfide (FeS2) / Copper Iron Sulfide (CuFeS2)
Pyrite Geode
Iron Disulfide (FeS2)
Howlite
Calcium borosilicate hydroxide (Ca2B5SiO9(OH)5)
Optical Calcite (Iceland Spar)
Calcite (Calcium Carbonate, CaCO3)
Gneiss
Gneiss (High-grade metamorphic rock)
Barite
Barium Sulfate (BaSO4)
Potassium Feldspar and Quartz
KAlSi3O8 (Potassium Feldspar) and SiO2 (Quartz)
Quartz
Silicon Dioxide (SiO2)
Blue Calcite
Calcium Carbonate (CaCO3)
Sandy Ironstone
Ferruginous Sandstone
Orange Calcite
Calcite (Calcium Carbonate, CaCO3)
Optical Calcite (Iceland Spar)
Calcite (Calcium Carbonate, CaCO3)
Quartz
Silicon dioxide (SiO2)
Manganese Oxide Crust on Limestone
Manganese Oxides (e.g., Pyrolusite MnO2 or Romanechite) on CaCO3
Banded Sandstone (Wonderstone)
Sandstone with Liesegang Rings (SiO2 with Iron Oxides)
Chert (Hagstone/Gasket Rock variant)
Chert (SiO2)
Glauconitic Sandstone
Glauconitic arenite (contains (K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2)
Ferruginous Sandstone
Arenite with Iron-oxide cement (composed of Quartz and Limonite/Hematite)
Chert (Flint)
Microcrystalline quartz (SiO2)
Jasper or Agate-bearing Chert
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
Chert (Limestone-based)
Silicon Dioxide (SiO2)
Shale or Argillite
Shale (fine-grained clastic sedimentary rock) or Argillite (low-grade metamorphic rock derived from shale)
Sandstone (with Limonite staining)
Arenite (FeOx-rich)
Chert (specifically Jasper or Flint type)
Microcrystalline Quartz (SiO2)
Sandstone (Ferruginous)
Arenite (Fe-rich)
Sandstone
Arenite (primarily SiO2 with various cementing agents)
Sandstone (likely Graywacke or Lithic Sandstone)
Arenite / Wacke (SiO2 based with lithic fragments)
Sandstone (Quartzose)
Arenite (SiO2 principal)
Sandstone (Quartzite-rich Pebble)
Arenite (composed primarily of SiO2)
Sandstone (Ferruginous)
Arenite (primarily SiO2 with iron oxide cement)
Limestone
Calcium Carbonate (CaCO3)