Fluorite
Calcium Fluoride (CaF2)
Category
Browse sedimentary (fossilized) specimens identified by the Rock Identifier community.
Fluorite
Calcium Fluoride (CaF2)
Marble
Recrystallized Calcite (CaCO3)
Jasper
Silicon dioxide (SiO2) with impurities
Quartz (Milky/Crystalline variety)
Silicon Dioxide (SiO2)
Carnelian (Red Agate)
Chalcedony (SiO2 with Iron Oxide impurities)
Quartz (Variety: Citrine or Tumbled Chalcedony)
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)
Green Chalcedony
Silicon Dioxide (SiO2) with trace minerals
Limonite (Iron Ore)
Limonite (FeO(OH)·nH2O)
Orange Calcite (Mexican Onyx)
Calcium Carbonate (CaCO3)
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)
Onyx Marble (Banded Calcite)
Calcite (Calcium Carbonate, CaCO3)
Barite
Barium Sulfate (BaSO4)
Potassium Feldspar and Quartz
KAlSi3O8 (Potassium Feldspar) and SiO2 (Quartz)
Chalcedony (Agate/Quartz)
Silicon Dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Blue Chalcedony
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Blue Calcite
Calcium Carbonate (CaCO3)
Mixed collection of minerals and rocks (Jasper, Carnelian, Granite, and Quartz)
Silicon Dioxide (SiO2) with varying impurities for silicates and igneous aggregates
Blue Chalcedony
Silicon Dioxide (SiO2)
Sandy Ironstone
Ferruginous Sandstone
Carnelian and White Quartz Bracelet
Silicon Dioxide (SiO2) - specifically Carnelian (Chalcedony) and Rock Crystal/Snow Quartz
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
Dendritic Agate or Tree Agate
Silicon Dioxide (SiO2) with impurities of manganese or iron oxide
Conglomerate
Clastic Conglomerate (Lithic-rich)
Ironstone with Pyrite
Ferruginous Sandstone (Fe2O3) with minor Sulfide minerals (FeS2)
Petrified Wood
Silicified Wood (SiO2 - Silicon Dioxide)
Ferruginous Sandstone (Ironstone)
Ferruginous Sandstone / Limonite-cemented Quartz Sandstone
Chert (Jasper/Flint variant)
Silicon Dioxide (SiO2)