Rhodochrosite with Pyrite and Quartz
Manganese Carbonate (MnCO3)
Category
Browse organic gemstone (often associated with sedimentary sequences) specimens identified by the Rock Identifier community.
Rhodochrosite with Pyrite and Quartz
Manganese Carbonate (MnCO3)
Banded Chert
Microcrystalline Quartz (SiO2)
Chert (specifically Flint or Dark Chert)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Banded Chert (River Cobble)
Microcrystalline Quartz (SiO2)
Bituminous Coal
Bituminous coal (Organic Sedimentary Rock)
Chert (Yellow Jasper/Flint)
Microcrystalline Quartz (SiO2)
Raw Diamond
Diamond (pure Carbon, C)
Chalcedony (Yellow Agate)
Cryptocrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (primarily Chalcedony or Quartz, SiO2)
Malachite
Copper carbonate hydroxide [Cu2CO3(OH)2]
Limestone (Fossiliferous)
Calcium Carbonate (CaCO3) - Bioclastic Limestone
Jasper (Banded Jasper)
Silicon Dioxide (SiO2) with impurities
Graywacke (Sandstone)
Graywacke Sandstone
Fossiliferous Limestone
Calcareous biomicrite / Bioclastic limestone
Greywacke
Dirty Sandstone (Lithic wacke)
Green Jasper
Silicon Dioxide (SiO2) with iron silicate inclusions
Pink Banded Onyx (Mexican Onyx / Calcite)
Calcite (CaCO3) - microcrystalline calcium carbonate
Chert (Nodule)
Microcrystalline Quartz (SiO2)
Zebra Rock / Zebra Marble
Banded Limestone-Marble Transition
Jasper pebble
Jasper (Silicon Dioxide, SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Aquamarine
Beryllium aluminum silicate (Be3Al2Si6O18)
Chert (and/or Chalcedony)
Microcrystalline Silica (SiO2)
Yellow Jasper
Microcrystalline Quartz with Iron Oxide (SiO2)
Red Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
Ironstone Concretion (Limonite/Goethite)
Iron oxide concretion (contains FeO(OH)·nH2O)
Petrified Wood
Silicified wood (Quartz/Chalcedony/Opal replacing organic matter)
Petrified Wood
Silicified Wood (SiO2)
Shale (or Mudstone)
Siltstone/Argillite (composed mainly of clay and silt-sized particles)
Petrified Wood
Silicified Wood (SiO2 - Quartz/Chalcendony replacing organic matter)
Dyed Pink Quartzite (Jadeite Simulant)
Silicon Dioxide (SiO2) with organic dye
Hematite
Iron(III) oxide (Fe2O3)
Green Moonstone (Garnierite)
Nickel-bearing Magnesium Silicate (often a mix of Serpentine and Talc/Chlorite groups)
Epidote-bearing Granite (Unakite-like)
Epidotized Granite
Chert (containing Calcite or Quartz inclusions)
Silicon Dioxide (SiO2) with varying mineral impurities
Chert (Cherty Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (varieties include Flint and Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (varietal Flint)
Chert (SiO2)
Sodalite
Sodalite - Na8(Al6Si6O24)Cl2
Banded Chert (Flint)
Cryptocrystalline Quartz (SiO2)
Green Jasper
Jasper (Silicates, SiO2)
Chert (Yellow/Brown variety)
Chert (SiO2)