Sandstone (likely Siltstone or fine-grained Sandstone)
Sedimentary Rock (Clastic)
Category
Browse not a rock specimens identified by the Rock Identifier community.
Sandstone (likely Siltstone or fine-grained Sandstone)
Sedimentary Rock (Clastic)
Basalt
Mafic Igneous Rock
Gneiss
Gneissic Metamorphic Rock
Banded Gneiss
Gneiss (Metamorphic Rock)
Slate
Foliated metamorphic rock
Basalt River Stone
Basaltic Igneous Rock
Siltstone or Mudstone
Argillaceous sedimentary rock
Peridotite
Peridotite (Ultramafic Rock)
Druzy Quartz Geode (likely Smokey Quartz variety)
Silicon Dioxide (SiO2) - specifically a geode formation lined with druzy quartz crystals, with a likely brownish hue indicating smokey quartz.
Basalt (Purple-tinted scoria/vesicular variety)
Extrusive mafic igneous rock (SiO2 range 45–52%)
Vesicular Basalt (Scoria)
Basalt (Vesicular)
Crushed Rock (Basalt)
Basalt (Aphanitic Mafic Igneous Rock)
Quartz Geode (Citrine or Iron-stained Quartz)
Silicon Dioxide (SiO2)
Quartzite (River Stone)
Quartzite
Gastropod Fossil (Snail Steinkern)
Class Gastropoda fossil, composed of Calcium Carbonate (CaCO3)
Quartz Vein in Siltstone
SiO2 (Quartz) on clastic sedimentary matrix
Chert / Flint
Cryptocrystalline quartz (SiO2)
Labradorite
Labradorite (Ca, Na)(Al, Si)4O8
Granodiorite
Granodiorite (containing Quartz, Plagioclase, Orthoclase, Biotite/Hornblende)
Unakite
Unakite (altered granite)
Unakite (or Epidote-rich Granite)
Unakite (composed of Epidote {Ca2(Al, Fe)3(SiO4)3(OH)}, Pink Orthoclase Feldspar {KAlSi3O8}, and Quartz {SiO2})
Garnet Schist
Almandine Garnet Schist (Fe3Al2(SiO4)3 in Schistose matrix)
Serpentine
Antigorite, Lizardite, or Chrysotile (Mg, Fe)3Si2O5(OH)4
Basalt Pebble
Basalt
Concrete / Anthropogenic Conglomerate
Man-made composite material (Portland cement, aggregate, and water)
Grey Agate (Tumbled)
Silicon Dioxide (SiO2)
Painted Pet Rock (Quartzite/Sandstone base)
Silicon Dioxide (SiO2) with anthropomorphic acrylic embellishments
Granodiorite (River Pebble)
Granodiorite
Quartz Pebble
Silicon Dioxide (SiO2)
Quartzite River Pebble
Quartzite (SiO2)
Chert (Common Opal variant)
Microcrystalline Quartz (SiO2)
Sandstone (likely Quartzose Sandstone)
Arenite (primarily SiO2)
Tiger's Eye (with Blue Tiger's Eye / Hawk's Eye)
Pseudomorph of Quartz after Crocidolite (SiO2 with inclusions)
River Stone (Granitic Gneiss)
Foliated Granitic Gneiss
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Fe2O3 staining)
Sandstone
Arenite (primarily SiO2)
Petrified Wood
Silicified Wood (SiO2)
Sandstone
Arenite (primarily SiO2)
Yellow Jasper
Silicon Dioxide (SiO2)
Quartz pebble with surface markings
Silicon Dioxide (SiO2)
Dendritic Agate
Silicon Dioxide (SiO2) with Manganese/Iron oxide inclusions
Jasper
Silicon Dioxide (SiO2) with impurities