Not a rock
Not a rock
Category
Browse rock specimens identified by the Rock Identifier community.
Not a rock
Not a rock
Not a rock
Not a rock
Not a rock
Not a rock
Wishing Stone (Quartz-veined Metamorphic/Sedimentary Rock)
Quartz Vein in Greywacke/Slate (SiO2 in host rock)
Angular gray rock fragments
Unidentified fine-grained rock; the image does not show diagnostic features sufficient for a specific identification
Granite (weathered cobble)
Granite; chiefly quartz, feldspar, and mica/amphibole
Granite
Intrusive Igneous Rock
Sandstone Pebble with Mineral Encrustation
Quartz Sandstone with Calcite/Halite Crust
Granite Pebble with Quartz Vein
Granite (Plutonic Igneous Rock) with Quartz (SiO2)
Quartz River Pebble
Silicon Dioxide (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Nephrite Jade
Nephrite
River Rock
Sedimentary clast
Shale
Laminated Mudstone (Shale)
Red Sandstone
Clastic Sandstone (typically Quartz-rich with Iron Oxide)
Gravel / Crushed Stone
Aggregate (mixed mineral rock fragments)
Conglomerate (possibly breccia/conglomeratic rock)
Polymictic conglomerate; composition and exact classification are uncertain from the image
Milky quartz vein in a host rock
Quartz (SiO₂), likely vein quartz; the gray host rock cannot be identified confidently from the image
Basalt with Quartz Vein
Mafic volcanic rock with hydrothermal SiO2 filling
Puddingstone (Quartzite Pebble)
Metaconglomerate / Jasper-Quartzite Pebble
Quartzite Pebble (River Siltstone/Quartzite)
Quartzite (SiO2 composition)
Likely altered volcanic rock (greenstone)
Chlorite–epidote–actinolite-rich metavolcanic rock; exact identification requires testing
Desert Rose
Gypsum (CaSO4·2H2O) or Barite (BaSO4)
Dark igneous rock, likely basalt or diabase, with a second purplish specimen
Basalt/diabase; exact identification is uncertain from the photograph
Crushed stone aggregate
Mixed lithic aggregate; individual fragments cannot be identified from the image
Quartz with Mafic/Chlorite Veins
Silicon Dioxide (SiO2) with Chlorite/Epidote cross-veining
Quartzite with Quartz Veining
Metamorphic Quartzite (SiO2)
Vesicular Basalt
Vesicular Basalt
Shale
Argillite / Shale
Fossilized Brachiopod or Gastropod in Chert/Limestone
Phylum Brachiopoda / Mollusca
Smooth river pebble (exact rock type indeterminate)
Unidentified rounded lithic clast; composition cannot be determined from the photograph
Wishing Stone (Quartz Vein in Greywacke / Basalt)
Quartz vein in host rock (e.g. Meta-basalt or Greywacke)
Quartz Vein in Metamorphic Rock
Quartz-veined Schist or Gneiss
Quartz Pebble
Silicon Dioxide (SiO2)
Granite Pebbles
Granite (composed primarily of Quartz SiO2, Feldspar (KAlSi3O8 – NaAlSi3O8 – CaAl2Si2O8), and Mica)
Likely banded gneiss
Quartz–feldspar–mica gneiss (tentative visual identification)
Granite
Intrusive Igneous Rock
Fossilized wood (petrified wood)
Silicified wood; commonly quartz/chalcedony (SiO₂) replacing wood tissue
Basalt Pebble and Shale Fragment
Extrusive volcanic rock and fine-grained sedimentary rock
Serpentine
Serpentine subgroup (Mg,Fe)3Si2O5(OH)4
Granite
Felsic intrusive igneous rock
Serpentine
(Mg,Fe)3Si2O5(OH)4