Quartzite
Metamorphic Rock consisting chiefly of Quartz (SiO2)
Category
Browse anthropogenic (man made material mimicking sedimentary rock) specimens identified by the Rock Identifier community.
Quartzite
Metamorphic Rock consisting chiefly of Quartz (SiO2)
Quartz Mica Schist
Mica-Quartz Schist (Chemical: SiO2 + KAl2(AlSi3O10)(OH)2)
River Rock
Sedimentary Rock (various compositions)
Coquina
Bioclastic Limestone
Shale
Fissile Clay-dominant Mudrock (SiO2, Al2O3, K2O, Na2O, CaO, MgO)
Rough Agate/Chert Nodules
Cryptocrystalline Quartz (SiO2)
Red Sandstone
Arenite with Hematite cementation
Red Jasper
Silicon Dioxide (SiO2)
Magnetite (Lodestone)
Iron(II,III) oxide (Fe3O4)
Siltstone/Sandstone (possibly Wonderstone or Picture Sandstone)
Clastic Sedimentary Rock (primarily SiO2 with Iron Oxide inclusions)
Chert (variations include Flint or Jasper)
Cryptocrystalline Quartz (SiO2)
Milky Quartz in Conglomerate Matrix
Silicon Dioxide (SiO2) within Clastic Sedimentary Rock
Sandstone (with Iron Staining)
Clastic sedimentary rock (primarily Quartz - SiO2)
Pebble (likely Quartz or Chert)
SiO₂ (Silicon Dioxide) - referring to the likely main mineral composition, Quartz. If it's chert, the scientific name remains SiO₂ with a microcrystalline structure.
Brecciated jasper/chalcedony (iron-stained silica)
Microcrystalline quartz, SiO₂, with iron-oxide inclusions
Chert (Jasper)
Microcrystalline Quartz (SiO2) with hematite impurities
Rounded reddish-brown pebble
Likely ferruginous sandstone or iron-rich quartzite; exact identification requires a fresh surface and tests
Petrified Wood
Silicified wood (primarily quartz, SiO2)
Jasper
Silicon Dioxide (SiO2)
Red Jasper / Chert
Silicon Dioxide (SiO2) with Iron Oxide inclusions
Chert / Jasper
Microcrystalline Quartz (SiO2)
Ferruginous Breccia
Breccia with Iron-rich (Hematite/Goethite) Matrix
Chert Nodule (Commonly known as Flint or River Rock)
Silicon Dioxide (SiO2)
Fossilized bivalve shell fragment
Fossil Mollusca, likely a bivalve (class Bivalvia); exact genus cannot be determined from the image
Polygenetic Breccia
Clastic Breccia (containing lithic fragments in a fine-grained matrix)
Chert (variant of Flint)
Chert (SiO2)
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Fe2O3 cement)
Chert (and Flint)
Cryptocrystalline Quartz (SiO2)
Banded Chert (likely Flint or Jasper variety)
Silicon Dioxide (SiO2)
Chert
Chert (Microcrystalline Quartz, SiO2)
Quartz Geode
Crystalline Silicon Dioxide (SiO2) in a Geode
Sandstone (Pebble/Conglomerate fragment)
Sandstone (clastic sedimentary rock)
Chert (Jasper/Iron-stained Quartzite)
Silicon Dioxide (SiO2)
Fossiliferous Limestone
Calcite-rich Sedimentary Rock (CaCO3)
Biotite granite (weathered granitic rock)
Granite; chiefly quartz (SiO₂), feldspar, and biotite mica
Sandstone with Fossil Leaf Impression
Sedimentary rock (Sandstone/Siltstone matrix) with Carbonaceous film fossil
Chert (Flint)
Microcrystalline Quartz (SiO2)
Weathered sandstone or iron-stained sedimentary pebble
Quartz-rich sandstone; exact identification requires a fresh surface and tests
Gneiss
Gneiss
Green Jasper (with Quartz veining)
Jasper (Silica-rich microcrystalline variety of Quartz), formula: SiO2
Red Jasper
Jasper (variety of Chert) - SiO2
White calcite (likely tumbled calcite or marble fragment)
Calcite, calcium carbonate (CaCO₃); if the specimen is granular and rock-like, it may be marble, a calcite-rich metamorphic rock