Limestone
Calcium Carbonate (CaCO3)
sedimentary
Category
Rock (Likely Sedimentary)
Browse rock (likely sedimentary) specimens identified by the Rock Identifier community.
Gneiss with Quartz Vein
Gneiss containing Quartz (SiO2) filler
metamorphic
Fossil Shark Tooth (embedded in matrix)
Lamniformes (likely Cretalamna or Squalicorax) within phosphatic/calcareous matrix
sedimentary
Wonderstone
Rhyolite (Silicon Dioxide with Iron Oxide impurities)
igneous
Mica Schist
Mica Schist (primarily Muscovite and Biotite composition)
metamorphic
Sandstone (Ferruginous)
Arenite (variable SiO2 with Fe2O3 staining)
sedimentary
Biotite Schist
Biotite Schist (K(Mg,Fe)3AlSi3O10(OH,F)2)
metamorphic
Sandstone (Quartz-rich)
Arenite (SiO2 based)
sedimentary
Ferruginous Sandstone (Ironstone)
Clastic Sedimentary Rock (composed of SiO2 with Fe2O3/FeO(OH) cement)
sedimentary
River Stone / Pebble
Clastic Sediment (composed largely of Quartz, Feldspar, and various rock fragments)
Mineral, Sediment
Red Jasper
Silicon Dioxide (SiO2) with Hematite impurities
sedimentary
Petrified Wood
Silicified wood (Quartz/Chalcedony - SiO2)
sedimentary
Bauxite
Bauxite (Al(OH)3, AlO(OH))
sedimentary
Crinaudite / Fossilized Crinoid Stem
Crinoid (Echinodermata) in a Calcitic/Siliceous Matrix
sedimentary
Purple Chalcedony (likely dyed Agate)
Silicon Dioxide (SiO2)
mineral
Gneiss (Metamorphic Rock)
Gneiss (variable mineral formula primarily containing Quartz, Feldspar, and Mica)
metamorphic
Druzzy Quartz on Matrix
Silicon Dioxide (SiO2)
mineral
Sandstone (Quartzose)
Arenite (primarily SiO2)
sedimentary
Sandstone (Weathered Pebble)
Arenite (primarily SiO2)
sedimentary
Sandstone (Ferruginous)
Sandstone (SiO2 with iron oxide inclusions)
sedimentary
Pyrite in Quartz
Iron Sulfide (FeS2) in Silicon Dioxide (SiO2)
Mineral
Chert (specifically Flint or Dark Chert)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Chert (varietal: Flint/Jasper mix)
Hydrous Silica (SiO2)
sedimentary
Milky Quartz
Quartz (Silica / Silicon Dioxide), SiO2
mineral
Sandstone
Arenite
sedimentary
Yellow Ochre / Limonite
Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)
mineral
Ferruginous Sandstone (Gozzan/Ironstone)
Arenite with Limonite/Goethite cement (FeO(OH)·nH2O)
sedimentary
Green Jasper
Silicon Dioxide (SiO2) with impurities
sedimentary
Dalmatian Stone
Peralkaline Feldsphathic Igneous Rock
igneous
Ferruginous Sandstone (Ironstone)
Clastic sedimentary rock (SiO2 with Fe2O3/FeO(OH) cement)
sedimentary
Sandstone (with Feldspathic/Arkose qualities)
Arenite (primarily SiO2 with KAlSi3O8 components)
sedimentary
Goethite (Iron Ore)
Goethite (FeO(OH))
mineral
Sandstone Concretion
Moqui Marble / Iron-oxide Concretion (SiO2 with Hematite/Goethite)
sedimentary
Sandstone
Clastic Sedimentary Rock (composed of SiO2 grains)
sedimentary
Halite
Halite (Sodium Chloride, NaCl)
mineral
Chert (specifically Flint or Jasper variant)
Microcrystalline Quartz (SiO2)
sedimentary
Agate
Silicon dioxide (SiO2)
mineral
Schist with Schorl (Black Tourmaline)
NaFe3Al6(BO3)3Si6O18(OH)4 (Schorl)
metamorphic
Geode (unopened)
SiO2 - Chert-shelled concretion (mostly Quartz)
sedimentary
Agate
Silicon Dioxide (SiO2) - variety: Chalcedony
mineral
Banded Calcite (often sold as 'Mexican Onyx')
Calcite (Calcium Carbonate, CaCO3)
sedimentary
Jasper with Agate Inclusions
Jasper (Silicon Dioxide, SiO2) with Chalcedony/Agate
sedimentary