Quartzite Cobble
Metamorphic Quartzite (SiO2)
Category
Browse sedimentary (secondary classification: cryptocrystalline quartz) specimens identified by the Rock Identifier community.
Quartzite Cobble
Metamorphic Quartzite (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert (Common Opal/Jasper variety)
Silicon Dioxide (SiO2)
Carnelian Agate
Silicon Dioxide (SiO2) with iron oxide impurities
Blue Calcite
Calcium Carbonate (CaCO3)
Chert (Flint)
Microcrystalline Silica (SiO2)
Quartz (Vein Quartz)
Silicon Dioxide (SiO2)
Native Gold (in the form of jewelry)
Gold (Au)
Gold Flake
Native Gold (Au)
Jasper containing fossilized inclusions
Silicon Dioxide (SiO2) with trace impurities and biogenic inclusions
Blue Calcite
Calcium Carbonate (CaCO3)
Chert (often called Flint or River Stone)
Chert (SiO2)
Quartz (Milky or Iron-Stained)
Silicon Dioxide (SiO2)
Quartz with Iron Staining
Silicon Dioxide (SiO2) with iron oxide impurities
Red Jasper or Chert
Jasper (SiO2, a variety of chalcedony with iron oxide impurities), Chert (SiO2)
Quartz with Iron Staining
Silicon Dioxide (SiO2) with Ferruginous Oxides
Sandstone (with Iron Staining)
Clastic sedimentary rock (primarily SiO2)
Milky Quartz with Iron Inclusions
Silicon Dioxide (SiO2)
Quartz (Milky/Crystalline)
Silicon Dioxide (SiO2)
Chalcedony
Chalcedony (SiO₂)
Shiva Lingam
Cryptocrystalline Quartz (Jasproid/Sandstone) with Iron Oxide (Fe2O3)
Shiva Lingam
Cryptocrystalline Quartz (Jasper/Chalcedony) with Iron Oxide inclusions
Pink Botswana Agate
Silicon Dioxide (SiO₂), a cryptocrystalline variety of Quartz and Chalcedony
Jasper
Silicon Dioxide (SiO2) with iron and magnesium inclusions
Quartz with Hematite Inclusions
Silicon Dioxide (SiO2) with Ferric Oxide (Fe2O3)
Carnelian
Carnelian (a variety of Chalcedony, which is a microcrystalline quartz, SiO2)
Chert (includes Flint & Jasper)
Chert (Siliceous sedimentary rock, chemical formula SiO2)
Ferruginous Quartz (Iron-stained Quartz)
Silicon Dioxide with Iron Oxide (SiO2 + Fe2O3)
Yellow Aventurine
Silicon Dioxide (SiO2) with inclusions
Red Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
Agate
Silicon Dioxide (SiO2)
Limonite with Hematite
Limonite (FeO(OH)·nH2O) and Hematite (Fe2O3)
Rhodochrosite
Manganese carbonate (MnCO3)
Calcite
Calcium Carbonate (CaCO3)
Hematite
Iron(III) oxide (Fe2O3)
Limonite (Iron Stone/Goethite)
Limonite (mixture of hydrated iron oxides, primarily Goethite: α-FeO(OH))
Granite with Epidote
Granite, containing quartz, feldspar, and epidote
Chert (Quartz Variety)
Microcrystalline Silica (SiO2)
Chert (Jasper/Jasperoid)
Chert (chemically precipitated microcrystalline Quartz, SiO2)
Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, SiO2)
Jasper (Iron-stained)
Silicon Dioxide (SiO2) with iron oxide inclusions
Turquoise
Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)