Sandstone (likely Quartzose Sandstone)
Arenite (composed primarily of SiO2)
Category
Browse sedimentary or metamorphic (base substrate) specimens identified by the Rock Identifier community.
Sandstone (likely Quartzose Sandstone)
Arenite (composed primarily of SiO2)
Anthracite Coal
Anthracite (Carbon-based metamorphic rock, 86-97% C)
Pyrite
Iron Sulfide (FeS2)
Quartz Geode
Quartz (Silicon Dioxide, SiO2) Geode
Aura Quartz Geodes (Lab-Altered)
Silicon Dioxide (SiO2) with Metallic Vapor Deposition
Fossilized Brachiopod
Brachiopoda (e.g., Rhynchonellida or Spiriferida)
Dalmatian Jasper
Dalmatian Stone (comprised of Feldspar, Quartz, and Arfvedsonite)
Quartz Vein in Mica Schist
Quartz (SiO2) with Muscovite/Biotite Schist
Chert (Iron-stained)
Chert (Cryptocrystalline Silica, SiO2)
Limestone
Sedimentary Calcium Carbonate (CaCO3)
Sandstone
Arenite (primarily SiO2)
Chert
Microcrystalline silica (SiO2)
River Stone / Siltstone
Siltstone (composed of lithified silt)
Ruby
Corundum (Al2O3 with Chromium trace impurities)
Sandstone (likely with Borings or Vesicular Basalt)
Clastic Sedimentary Rock (Sandstone)
Limestone (with Iron-Oxide staining)
Sedimentary Calcium Carbonate (CaCO3)
Sandstone (Quartzose)
Arenite (primarily SiO2)
Sandstone
Arenite (composed primarily of SiO2)
Schist
Mica Schist (primarily composed of quartz, feldspar, and mica)
Limestone
Calcium Carbonate (CaCO3)
Quartzite
Quartzite (SiO2)
Pyrite Concretion (Grapestone)
Iron Sulfide (FeS2) Concretion
Polygenetic Conglomerate (Puddingstone)
Conglomerate (SiO2 matrix with mixed clasts)
Magnetite
Magnetite (Fe3O4)
Ruby in Fuchsite
Corundum (Al2O3) in Fuchsite (K(Al,Cr)3Si3O10(OH)2)
Schist (Micaceous)
Mica Schist
Mica Schist
Mica Schist
Mica Schist
Mica Schist (predominantly composed of Muscovite or Biotite silicates)
Schist
Mica Schist
Mica Schist
Crystalline Schist (often primarily Muscovite or Biotite sheet silicates)
Sandstone
Arenite (primarily SiO2)
Limestone
CaCO3 (Mainly Calcite or Aragonite)
Chert (variations include Flint or Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Sandstone (likely Siltstone)
Arenite or Siltstone (high SiO2 content)
Siltstone
Siltstone (primarily SiO2 with Al2O3)
Travertine
Terrestrial Sedimentary Limestone (CaCO3)
Anthracite Coal
Anthracite (Carbon-based organic sedimentary rock exposed to metamorphic heat/pressure; Chemical composition is approximately 86%–98% Carbon)
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
Conglomerate
Conglomerate (a clastic sedimentary rock)
Sandstone (with banding)
Arenite (primarily SiO2)
Sandstone (Quartz-rich)
Sandstone (SiO2 dominated)
Jasper (likely Brecciated or Multi-colored)
Jasper (SiO2)