Granite
Granite (phaneritic felsic intrusive rock)
Category
Browse organic structure (not a rock) specimens identified by the Rock Identifier community.
Granite
Granite (phaneritic felsic intrusive rock)
Sandstone
Arenite (primarily SiO2)
Gold Nugget
Native Gold (Au)
Kimberlite
Kimberlite (Potassic ultramafic volcanic rock)
Basalt
Basalt
Basalt
Basalt (Mafic volcanic rock)
Chert (Iron-stained)
Chert (Cryptocrystalline Silica, SiO2)
Quartz (likely Clear Quartz or Rock Crystal)
Quartz (SiO2)
Unakite
Unakite (Epidotized Granite)
Druzy Quartz Geode (Vug)
Silicon Dioxide (SiO2)
Chert (and/or Siltstone River Pebble)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Basalt River Pebble
Basalt (fine-grained mafic igneous rock)
Red Granite
Felsic Plutonic Rock (Granite)
Ferruginous Sandstone
Clastic sedimentary rock (SiO2 with Fe2O3/FeO(OH) cement)
Quartz Vein in Host Rock
Silicon Dioxide (SiO2) within Metasedimentary or Igneous matrix
Quartz (Druzy)
Silicon Dioxide (SiO2)
Clear Quartz
Quartz (Silicon Dioxide, SiO2)
Sandstone with Liesegang Rings
Arenite with Iron Oxide Concretions
Serpentine (Nephrite-like Serpentine)
Serpentinite (Hydrous magnesium iron phyllosilicate)
Basalt
Extrusive mafic igneous rock
Basalt with Limonite stains
Extrusive mafic igneous rock; Limonite (FeO(OH)·nH2O)
Serpentine
Serpentine group ((Mg, Fe, Ni, Al, Zn, Mn)2-3(Si, Al, Fe)2O5(OH)4)
Basalt
Basalt (Aphanitic Mafic Igneous Rock)
Limestone
Calcareous sedimentary rock (CaCO3)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Fire Opal (Common/Precious in Matrix)
Hydrated Silica (SiO2·nH2O)
Ferruginous Quartz
Quartz with Iron Oxide inclusions (SiO2 + Fe2O3)
Dalmation Stone (often called Dalmatian Jasper)
Antiperthite-rich Microgranite
Granite
Granite (composed primarily of Quartz, Feldspar, and Mica)
Granite
Phaneritic plutonic rock (Quartz + Feldspar + Mica)
Pumice
Pumice (Vesicular Rhyolite/Andesite)
Unakite
Unakite (Altered Granite consisting of Orthoclase KAlSi3O8, Epidote Ca2(Al,Fe)3(SiO4)3(OH), and Quartz SiO2)
Serpentine
Antigorite / Lizardite / Chrysotile mix; (Mg, Fe)3Si2O5(OH)4
River Rock (Quartzite)
Quartzite (SiO2)
Granite (likely a river or beach pebble)
Granite (a felsic intrusive igneous rock primarily composed of quartz, feldspar, and mica)
Ocean Jasper
Orbicular Jasper (Silicon Dioxide with impurities), SiO2
Chert (Field Stone/Pebble)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Yellow Quartz (Citrine or Iron-Stained Quartz)
Silicon Dioxide (SiO2)
Quartz (Milky/Common)
Silicon Dioxide (SiO2)
Olivine Peridotite
Peridotite (comprising Olivine (Mg,Fe)2SiO4 and Pyroxene)