Banded Calcite (often sold as 'Mexican Onyx' or 'Green Onyx')
Calcite (CaCO3)
Category
Browse sedimentary (if natural jasper) or artificial (if slag) specimens identified by the Rock Identifier community.
Banded Calcite (often sold as 'Mexican Onyx' or 'Green Onyx')
Calcite (CaCO3)
Amber
Succinite (a fossilized organic resin containing succinic acid)
Zebra Marble
Metamorphosed Alabaster/Limestone (CaCO3)
Dyed Agate
Silicon Dioxide (SiO2) with artificial pigment
Pyrite
Iron Sulfide (FeS2)
Schist (specifically Mica Schist)
Mica Schist (primarily composed of Muscovite KAl2(AlSi3O10)(OH)2 and Biotite)
Quartz Geode Fragment
Silicon Dioxide (SiO2)
Orange Satin Spar (Satin Spar Selenite)
Satin Spar - Hydrous Calcium Sulfate (CaSO4·2H2O)
Quartzite Cobble
Quartzite (primarily SiO2)
Chert (Tan/Yellow variety)
Microcrystalline quartz (SiO2)
Chalcedony (Botryoidal)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Quartzite Pebble
Quartzite (primarily SiO2)
Sandstone (likely Siltstone variety)
Arenite / Siltstone (primary mineral SiO2)
Chert (Tan/Yellow variety)
Microcrystalline Quartz (SiO2)
Sandstone (Water-worn Pebble)
Clastic Sedimentary Rock (primarily SiO2)
Sandstone
Arenite (primarily SiO2 - Silicon Dioxide)
Chert (often called Flint when dark)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Porphyry (likely Porphyritic Andesite or Basalt)
Porphyritic Igneous Rock
Chert (Tan/Buff Chert)
Microcrystalline Quartz (SiO2)
Sandstone
Arenite (primarily composed of SiO2)
Quartz Geode in Chert/Limestone Matrix
Silicon Dioxide (SiO2) within Sedimentary Host Rock
Yellow Calcite
Calcite (Calcium Carbonate, CaCO3)
Fossilized Oyster Shell
Gryphaea or Crassostrea fossil (Calcium Carbonate, CaCO3)
Sandstone (specifically Arkose or Ferruginous Sandstone)
Sandstone (SiO2 with iron oxide inclusions)
Chert (specifically a Worked Flint/Knapped Flake)
Chert / Flint (Microcrystalline Quartz, SiO2)
Chert / Flint
Cryptocrystalline Quartz (Silicon Dioxide, SiO2)
Quartzite River Rock
Quartzite (primarily SiO2)
Chert (specifically a nodule with Chalcendony/Agate banding)
Microcrystalline Quartz (SiO2)
Chert (Honey Chert / Flint)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
Moqui Marble (Moqui Ball)
Ironstone Concretion (Goethite/Hematite cemented Sandstone)
Geode (Unopened)
Siliceous Septarian Concretion / Geode (SiO2)
Diamond (Set in jewelry)
Cubic Carbon (C)
Agate
Chalcedony (SiO2)
Ferruginous Sandstone
Arenite with Iron-Oxide cement (primarily Fe2O3 • nH2O)
Barite Rose on Marcasite
Barium Sulfate (BaSO4) on Iron Sulfide (FeS2)
Quartz Geode Fragment
Silicon Dioxide (SiO2)
Fossil Coral (Honeycomb Coral)
Favosites (extinct genus of Tabulate coral)
Fossiliferous Limestone with Brachiopods
Calcium Carbonate (CaCO3) with fossilized Brachiopoda sp. (likely Order Spiriferida or Rhynchonellida)
Limestone (specifically Fossiliferous Limestone)
Calcium Carbonate (CaCO3)
Crinoid Fossil in Limestone
Crinoid (Class Crinoidea) in Fossiliferous Limestone (CaCO3)
Wishing Stone
Greenschist or Basalt with Quartz/Calcite Vein
Agatized Fossil or Chalcedony Nodule
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz