Agate (Chalcedony)
Cryptocrystalline Silica or Silicon Dioxide (SiO2)
mineral
Category
Not A Rock Or Mineral
Browse not a rock or mineral specimens identified by the Rock Identifier community.
Banded Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
metamorphic
Granite
Granite (Phaneritic intrusive igneous rock)
igneous
Amygdaloidal Rhyolite
Amygdaloidal Rhyolite (Felsic volcanic rock)
igneous
Conglomerate
Clastic sedimentary rock (Conglomerate)
sedimentary
Sandstone (Micaceous/Feldspathic variant)
Arenite (specifically subarkose or lithic arenite)
sedimentary
Sandstone (with Liesegang rings or Oxidation)
Arenite (primarily Quartz SiO2 with Iron Oxide Fe2O3 staining)
sedimentary
Greywacke (River Slikkenstone)
Greywacke (Impure Sandstone)
sedimentary
Dalmatian Stone (commonly called Dalmatian Jasper)
Peralkaline Rock (mixed Feldspar, Quartz, and Arfvedsonite)
igneous
Grey River Stone (Quartz-rich Quartzite/Siltstone)
Quartzite / Meta-siltstone (primarily SiO2)
Metamorphic (low-grade)
Quartz / Quartzite
Silicon Dioxide (SiO2)
metamorphic
Schist (Garnet-Mica Schist)
Garnet-Mica Schist (X-Y)3Z2(SiO4)3
metamorphic
River Stone (likely Mudstone or Siltstone)
Lutite (Clastic sedimentary rock composed of clay and silt-sized particles)
sedimentary
Basalt
Basalt
igneous
Snowflake Obsidian
Volcanic Glass with Cristobalite inclusions
igneous
Petrified Wood
Silicified wood (primarily Silicon Dioxide - SiO2)
metamorphic
Green Aventurine
Silicon Dioxide (SiO2) with Fuchsite inclusions
metamorphic
Ruby in Zoisite
Ruby (Corundum, Al2O3) in Zoisite (Calcium aluminum silicate hydroxide, Ca2Al3(SiO4)3(OH)) with some Hornblende
Metamorphic Rock (specifically a rock composed of minerals)
Granite
Granite (Felsic Plutonic Rock)
igneous
Sandstone (Water-worn Pebble)
Clastic Sedimentary Rock (primarily SiO2)
sedimentary
Red Sandstone
Arenite (with Iron Oxide cement)
sedimentary
Granite (tumbled pebble)
Granite (Plutonic Igneous Rock)
Igneous Rock
Rough Dark Green Sapphire
Corundum (Al2O3)
mineral
Basalt
Basalt (Aphanitic Mafic Igneous Rock)
igneous
Quartz / Calcite Vein Rock
Silicon Dioxide (SiO2) or Calcium Carbonate (CaCO3)
mineral
Quartz (Double-Terminated)
Silicon Dioxide (SiO2)
mineral
Agate (specifically Carnelian or Honey Agate)
Silicon Dioxide (SiO2)
Mineral
Quartz on Host Rock
Silicon Dioxide (SiO2)
Mineral Specimen
Sandstone (Quartzose)
Arenite (composed primarily of SiO2)
sedimentary
Orange Quartzite (River Pebble)
Quartzite (SiO2 with iron oxide inclusions)
metamorphic
Jasper (likely Ocean Jasper or Variegated Jasper)
Silicon Dioxide (SiO2) with impurities
sedimentary
Lunar Meteorite (Feldspathic Breccia)
Achondrite, Lunar Meteorite (Feldspathic Breccia)
igneous
Aventurine
Silicon Dioxide (SiO2) with Fuchsite inclusions
metamorphic
Unknown Rock Specimen
igneous
Conglomerate
Conglomerate (clastic sedimentary rock)
sedimentary
Milky Quartz
Quartz / Silicon Dioxide (SiO2)
mineral
Riverstone Quartzite (Water-worn Siltstone/Quartzite)
Metamorphosed Quartz-rich Arenite (SiO2)
metamorphic
Serpentinite
Serpentinite (composed primarily of serpentine-group minerals like antigorite, chrysotile, and lizardite; chemical formula varies but generally Mg3Si2O5(OH)4)
Metamorphic Rock
Basalt with Quartz/Epidote Vein
Mafic volcanic rock (formula primarily (Mg, Fe)2SiO4 and CaAl2Si2O8)
igneous
Ferruginous Sandstone Pebble
Arenite with Iron-Oxide Cement (SiO2 with Fe2O3/FeO(OH) staining)
sedimentary
Chert / Flint
Chert (Silicon Dioxide, SiO2)
sedimentary
Pink Granite
Phaneritic Plutonic Felsic Rock (Granite)
igneous