Geode (Unopened)
Crystalline Quartz or Chalcedony filled Geode (SiO2)
sedimentary
Community gallery
All rocks & minerals
Every specimen the Rock Identifier community has discovered, from desert agates to deep-sea basalts.
Chalcedony (Agate/Chert variety)
Silicon Dioxide (SiO2)
mineral
Conglomerate
Conglomerate (clastic sedimentary rock)
sedimentary
Chert Breccia (with Iron Staining)
Microcrystalline Quartz (SiO2) with iron oxides (Limonite/Goethite)
sedimentary
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Nephrite Jade
Nephrite (Ca2(Mg,Fe)5Si8O22(OH)2)
metamorphic
Garnet-Bearing Schist
Almandine Garnet Schist
metamorphic
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Fe2O3 staining)
sedimentary
Petoskey Stone (Fossilized Coral)
Hexagonaria percarinata
sedimentary
Green Aventurine
Quartz variety (SiO2 with inclusions of Fuchsite)
mineral
Calcite
Calcium Carbonate (CaCO3)
mineral
Jasper
Silicon dioxide (SiO2)
sedimentary
Fossiliferous Limestone (Crinoidal Limestone)
Bioclastic grainstone (CaCO3)
sedimentary
Amazonite
Amazonite (Microcline Feldspar) K(AlSi3O8)
mineral
Yellow Jasper
Silicon Dioxide (SiO2)
sedimentary
Granite Pebble with Quartz/Mafic Vein
Felsic Igneous Rock (Granitic)
igneous
Sandstone (Quartzose)
Arenite (SiO2 based)
sedimentary
Gneiss
Gneiss
metamorphic
Chert (specifically Gray Chert/Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Schist with Quartz
Mica Schist (contains Muscovite/Biotite and Quartz SiO2)
metamorphic
Quartzite
Quartzite (SiO2)
metamorphic
Red Sandstone
Arenite with Hematite (Fe2O3)
sedimentary
Agate Geode Node
Cryptocrystalline Quartz (SiO2)
mineral
Banded Iron Formation (BIF)
Banded Iron Formation (SiO2 + Fe2O3)
sedimentary
Lake Superior Agate
Agate (Cryptocrystalline variety of Quartz, SiO2)
mineral
Glauconitic Sandstone
Glauconitic Sandstane (containing K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2)
sedimentary
Serpentine
Antigorite, Lizardite, or Chrysotile (Mg, Fe)3Si2O5(OH)4
metamorphic
Serpentine
Serpentine Group (Mg, Fe, Ni, Al, Zn, Mn)2-3(Si, Al, Fe)2O5(OH)4
metamorphic
Chert (Yellow Jasper)
Microcrystalline Quartz (SiO2)
sedimentary
Limonite-stained Quartz
Silicon Dioxide (SiO2) with Hydrated Iron Oxide (FeO(OH)·nH2O) coatings
mineral
Chert (Nodule)
Chert (Silicon Dioxide, SiO2)
sedimentary
Agate
Cryptocrystalline Quartz (SiO2)
mineral
Black Onyx
Silicon Dioxide (SiO2) - variety of Chalcedony
mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Chert (Nodule)
Microcrystalline Quartz (SiO2)
sedimentary
Obsidian
Obsidian (Volcanic Glass)
igneous
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Granite
Phaneritic intrusive igneous rock (Composition: Quartz, Feldspar, Mica)
igneous
Quartzite
Quartzite (primarily SiO2)
metamorphic
Porphyritic Andesite
Andesite (Porphyritic texture)
igneous