Granite
Phaneritic plutonic rock (SiO2 range 65-75%)
Category
Browse igneous and sedimentary specimens identified by the Rock Identifier community.
Granite
Phaneritic plutonic rock (SiO2 range 65-75%)
Milky Quartz with Iron Inclusions
Silicon Dioxide (SiO2)
Quartz (Iron-Stained)
Silicon Dioxide (SiO2)
Mahogany Obsidian
Volcanic Glass with Hematite or Magnetite inclusions (SiO2 + Fe2O3)
Milky Quartz
Silicon Dioxide (SiO2)
Granite
Granite (Mainly Quartz SiO2 and Feldspar KAlSi3O8)
Granite
Phaneritic Felsic Intrusive Rock
Quartz Geode
Silicon Dioxide (SiO2) in a Geode body
Banded Sandstone (Zebra Stone)
Arenite with Iron Oxide Banding (Liesegang rings)
Sandstone with Ironstone Concretion
Arenite with Hematite/Goethite nodules (Fe2O3 / FeO(OH))
Quartz (in matrix)
Quartz (SiO₂)
Granite
Granite (a plutonic rock)
Sandstone Concretion
Sedimentary concretion
Sandstone or Limestone
Sedimentary Rock
Aquamarine
Beryl (Be3Al2Si6O18 with Fe2+ impurities)
Sandstone
Arenite (primarily SiO2)
Shale
Fissile mudrock (composed of clay-sized particles and detrital grains)
Shale
Fissile Mudstone (primarily composed of phyllosilicate minerals like kaolinite, montmorillonite, and illite)
Shale
Clastic sedimentary rock (primarily clay and silt minerals)
Shale
Shale (Lutite)
Shale
Fissile mudstone (rich in clay minerals and quartz)
Shale
Fissile mudrock (composed primarily of clay minerals and quartz)
Quartz in Basalt (Xenocryst)
Silicon Dioxide (SiO2) in Mafic Igneous Volcanic Rock
Hypersthene
Hypersthene ((Mg,Fe)SiO₃)
Halite (Rock Salt)
Halite (Sodium Chloride, NaCl)
Quartz Vein in Host Rock
Silicon Dioxide (SiO2) within Sedimentary/Metamorphic Matrix
Granite Pebble
Granite (a plutonic igneous rock composed primarily of quartz, feldspar, and mica/amphibole)
Olivine in Basalt matrix
Olivine (Magnesium Iron Silicate - (Mg, Fe)2SiO4)
Amygdaloidal Basalt
Vesicular-Amygdaloidal Basalt (Mafic Extrusive)
Milky Quartz with Iron Staining
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Mixed Tumbled Gemstones (Agate, Aventurine, Pyrite, etc.)
Multiple (principally Silicon Dioxide SiO2 and Iron Disulfide FeS2)
Granite
Granite (Phaneritic Igneous Rock)
Milky Quartz
Quartz (SiO₂)
Greenschist
Greenschist facies rock
Banded Gneiss (River Rock/Pebble)
Gneiss (specifically a banded variety often found as a river rock)
Flesh-toned Siltstone
Siltstone (composed of microscopic Quartz and Feldspar grains)
Jasper (specifically Polychrome or Desert Jasper)
Silicon Dioxide (SiO2) with impurities
Shale
Shale (fine-grained clastic sedimentary rock)
Quartz
Quartz (SiO2)
Milky Quartz with Iron Staining
Quartz (Silicon Dioxide, SiO2)