Granite Cobble
Phaneritic Plutonic Felsic Rock
Category
Browse sedimentary rock (technically a microcrystalline quartz mineral aggregate) specimens identified by the Rock Identifier community.
Granite Cobble
Phaneritic Plutonic Felsic Rock
Quartzite Pebbles
Quartzite (SiO2)
Quartzite
Quartzite (SiO2)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Granite (weathered pebble)
Granite (plutonic igneous rock)
Gneiss (specifically a weathered Amphibolite or Garnet Gneiss)
Gneiss (complex silicate composition)
Gneiss (specifically Biotite Gneiss)
Gneiss (high-grade metamorphic rock primarily composed of Silicates)
Quartz
Silicon Dioxide (SiO2)
Quartz (Rose or Clear variety)
Silicon Dioxide (SiO2)
Limonite and Goethite (Ironstone)
Hydrous Iron Oxide Mixture (FeO(OH)·nH2O)
Red Jasper (Skull Carving)
Jasper, a cryptocrystalline variety of Quartz (SiO2)
Quartzite Cobble
Quartzite (primarily SiO2)
Quartz pebble (Quartztite fragment)
Silicon Dioxide (SiO2)
Red Sandstone
Arenite (Fe2O3 rich)
River Stone (Basalt)
Basalt (Aphanitic Mafic Igneous Rock)
Sandstone (Ferruginous)
Sandstone (SiO2 with iron oxide inclusions)
Granite Pebble
Felsic Intrusive Igneous Rock (composed of Quartz, Alkali Feldspar, and Plagioclase)
Mica Schist
Mica Schist (Schistose metamorphic rock rich in Muscovite/Biotite)
Granite
Phaneritic Felsic Igneous Rock
Sandstone (Quartzose Sandstone)
Arenite (SiO2)
Mixed Tumbled Stones (Mostly Agate, Jasper, and Quartz)
Silicon Dioxide (SiO2)
Jasper River Pebble
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Granite
Granite
Quartzite pebble
Metamorphic rock (mainly SiO2)
Quartzite
Quartzite (primarily SiO2)
Quartz / Quartzite
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide - SiO2)
Basalt with Quartz Veins
Basalt (composition: SiO2, MgO, FeO, Al2O3, CaO)
Snakeskin Agate
Agate (Cryptocrystalline Quartz, SiO2)
Grey Basalt Pebble
Basalt (Aphanitic Mafic Volcanic Rock)
Granite
Granite (Mainly Quartz, Feldspar, and Mica)
Basalt Beach Pebble
Basalt (Aphanitic Mafic Igneous Rock)
Basalt
Basalt (Mafic Extrusive Igneous Rock)
Basalt with Quartz/Quartzite Veins
Aphanitic Mafic Volcanic Rock with Siliceous Infillings
Agate (specifically Carnelian Agate or Lake Superior style Agate)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
White Quartz Pebble
Silicon Dioxide (SiO2)
Basalt
Basalt (Aphanitic-fine grained mafic igneous rock)
Quartzite
Quartzite (SiO2 silicon dioxide)
Jasper with Quartz Veining
Silicon Dioxide (SiO2) - Cryptocrystalline Chalcedony
Gneiss
Gneiss
Limestone with Calcite Veining
Calcium Carbonate (CaCO3)
Tufa (Limestone)
Calcareous Tufa (CaCO3)