Sandstone, Quartzite, and River Pebbles
Silicon Dioxide (SiO2) based Sedimentary/Metamorphic structures
Sedimentary and Metamorphic
Category
Sedimentary Rock (Specifically A Clastic Sedimentary Rock Formed Into A Cobble)
Browse sedimentary rock (specifically a clastic sedimentary rock formed into a cobble) specimens identified by the Rock Identifier community.
Coquina or Fossiliferous Limestone
Biogenic Limestone (Calcite/Aragonite CaCO3)
sedimentary
Basalt
Basalt (Mafic volcanic rock)
igneous
Sandstone (likely Quartzose Sandstone pebble)
Arenite (primarily SiO2)
sedimentary
Banded Agate (specifically Carnelian Agate slice)
Chalcedony (cryptocrystalline variety of Quartz), SiO2
mineral
Red Sandstone
Arenite (with Iron Oxide)
sedimentary
Sandstone
Sandstone (principally SiO2)
sedimentary
Ferruginous Sandstone (Ironstone)
Clastic Sedimentary Rock (composed of SiO2 with Fe2O3/FeO(OH) cement)
sedimentary
Sandstone with Quartz Veining
Arenite with hydrothermal quartz (SiO2)
sedimentary
Shale or Argillite
Shale (sedimentary) / Argillite (metamorphic)
Sedimentary or Metamorphic (low-grade)
Mookaite Jasper
Siliceous sedimentary rock (variety of Jasper/Chert)
Sedimentary Rock
Red Sandstone
Arenite (with Iron Oxide cement)
sedimentary
Breccia
Breccia
sedimentary
Arkosic Sandstone
Arkose
sedimentary
Granite Cobble
Phaneritic Felsic Igneous Rock (Granite)
igneous
Coquina (Fossiliferous Limestone)
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Quartzite with Iron Inclusions
Metamorphic Quartzite (SiO2 with Fe2O3 trace impurities)
metamorphic
Red Sandstone (Iron-rich)
Ferruginous Sandstone (variable formula, primarily SiO2 + Fe2O3)
sedimentary
Sandstone with Manganese Dendrites/Oxide coatings
Arenite with Pyrolusite and Romanechite (MnO2)
sedimentary
Sandstone with Bedding Planes
Arenite (Sedimentary rock composed primarily of sand-sized minerals)
sedimentary
River Pebble Gravel
Hydrothermally modified Clastic Sediment (mainly Quartzite and Chert)
sedimentary
Chert (specifically Gray/Tan Bedded Chert)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Ferruginous Sandstone (Gritstone)
Arenite with Iron-Oxide Cement (SiO2 with Fe2O3 and FeO(OH))
sedimentary
Red Sandstone (Old Red Sandstone Pebble)
Arenite with iron oxide (Fe2O3) cement
sedimentary
Agate (specifically, a slice of a Blue Lace or Chalcedony Agate nodule)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
mineral
Red Sandstone
Arenite (with Iron Oxide / Hematite cementation)
sedimentary
Shale or Siltstone
Sedimentary Clastic Rock (Variable mineral composition including quartz and clay minerals)
sedimentary
Chert (Jasper transition)
Microcrystalline Quartz (SiO2)
sedimentary
Coquina
Bioclastic Limestone (Calcium Carbonate, CaCO3)
sedimentary
River Rock (Quartz-dominated)
Silicon Dioxide (SiO2) mixture with varied clastic sediments
sedimentary (alluvial deposit)
Chert (Jasper-like)
SiO2 (Cryptocrystalline Quartz)
Sedimentary
Wonderstone (Sandstone)
Liesegang Banded Sandstone (SiO2 dominated)
sedimentary
Granodiorite (River Rock / Cobble)
Granodiorite; Phaneritic intrusive igneous rock dominated by plagioclase, quartz, and hornblende/biotite
igneous
River Siltstone Pebble
Siltstone (primarily composed of silica and clay minerals)
sedimentary
Quartzite
Quartzite (primarily SiO2)
metamorphic
Red Sandstone
Sandstone (mainly SiO2 with Iron Oxide cement)
sedimentary
River Stone (likely Mudstone or Siltstone)
Lutite (Clastic sedimentary rock composed of clay and silt-sized particles)
sedimentary
Ferruginous Sandstone
Sandstone with iron oxide (Hematite/Limonite) cement
sedimentary
Red Sandstone
Arenite (with Iron Oxide pigmentation)
Sedimentary
Puddingstone (Jasper Conglomerate)
Conglomerate (specific type: Jasper Conglomerate or Hertfordshire Puddingstone)
Sedimentary
Sandstone
Arenite or Sandstone
Sedimentary Rock
Slate
Foliated Metamorphic Rock (Mainly composed of Quartz, Illite, Chlorite)
metamorphic