Sandstone
Arenite (SiO2 based)
sedimentary
Category
Organic Gemstone (Not A Rock Or Mineral In The Traditional Sense, But Bio Mineralized Material)
Browse organic gemstone (not a rock or mineral in the traditional sense, but bio mineralized material) specimens identified by the Rock Identifier community.
Sandstone
Arenite (composed primarily of SiO2)
sedimentary
Sandstone
Arenite (SiO2 based)
sedimentary
Sandstone
Arenite (SiO2 principal)
sedimentary
Sandstone (with Iron Staining)
Clastic sedimentary rock (primarily SiO2 with Fe2O3 oxides)
sedimentary
Granite
Granite (a felsic intrusive igneous rock)
Igneous Rock
Sandstone
Clastic Sedimentary Rock (composed mostly of quartz, SiO2)
sedimentary
Sandstone (Beach Pebble)
Clastic sedimentary rock (primarily Quartz and Feldspar)
sedimentary
Amazonite
Amazonite (KAlSi3O8, a triclinic variety of Potassium Feldspar)
mineral
Sandstone
Arenite (primarily SiO2)
sedimentary
Moss Agate
Silicon Dioxide (SiO2) with Manganese or Iron Oxide inclusions
mineral
Moss Agate
Chalcedony (Silicon Dioxide, SiO2) with inclusions
mineral
Sedimentary Sandstone (Sandstone Slab)
Arenite (SiO2 with Fe2O3 staining)
sedimentary
Sandstone
Arenite (SiO2 predominantly)
sedimentary
Quartz Geode
Silicon Dioxide (SiO2)
mineral
Quartz (Milky/Clear variety)
Silicon Dioxide (SiO2)
mineral
Chert (Jasper-bearing)
Microcrystalline silica (SiO2) with iron oxide inclusions
sedimentary
Sandstone (likely Ferruginous)
Arenite (SiO2 with iron oxide impurities)
sedimentary
Pyrite in Shale
Iron Sulfide (FeS2) in Sedimentary Matrix
mineral
Chert (Nodule)
Silicon Dioxide (SiO2)
sedimentary
Sandstone (likely Siltstone or fine-grained Sandstone)
Sedimentary Rock (Clastic)
sedimentary
Greenschist
Greenschist facies rock
Metamorphic
Sandstone (likely Quartz Sandstone)
Arenite (composed primarily of SiO2)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
mineral
Chert (Chert / Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Turquoise and Red Coral (with Grizzly Bear Claw)
Turquoise (CuAl6(PO4)4(OH)8·4H2O) and Precious Coral (Corallium rubrum)
mineral
Shale
Fissile Mudstone (Shale)
sedimentary
Fossilized Dinosaur Skull (Tyrannosaurus rex)
Tyrannosaurus rex (permineralized fossil), rich in Hydroxylapatite/Silica
sedimentary
Sandstone (with Iron Staining)
Clastic sedimentary rock (primarily SiO2 with Fe2O3 oxides)
sedimentary
Sandstone with Quarzite clasts
Arenite (SiO2 based)
sedimentary
Unakite
Unakite (Metasomatized Granite)
metamorphic
Jasper
Jasper (Silicon Dioxide, SiO2)
sedimentary
Sandstone (likely Greywacke or Lithic Sandstone)
Arenite / Wacke
sedimentary
Sandstone (Yellow/Siltstone variant)
Arenite (SiO2 primarily)
sedimentary
Breciated Limestone with Calcite Veins
Sedimentary Breccia (CaCO3)
sedimentary
Granite with Epidote
Granite, containing quartz, feldspar, and epidote
Igneous
Gneiss
Foliated Metamorphic Rock (Gneiss)
metamorphic
Agate (Moss or Dendritic Agate)
Chalcedony (Silicon Dioxide, SiO2)
mineral
Sandstone
Arenite (Sedimentary rock comprising sand-sized grains)
sedimentary
Quartz Vein in Siltstone
SiO2 (Quartz) on clastic sedimentary matrix
sedimentary
Amber
Resinite (Succinite if from the Baltic); Chemical Formula: C10H16O (approximate)
Organic Diamond/Gemstone (often associated with Sedimentary sequences)
Sandstone
Sandstone (lithified quartz arenite, arkose, graywacke, etc. depending on composition)
Sedimentary Rock