Milky Quartz
Silicon Dioxide (SiO2)
Category
Browse sedimentary or igneous specimens identified by the Rock Identifier community.
Milky Quartz
Silicon Dioxide (SiO2)
Sandstone
Clastic Sedimentary Rock (composed mostly of SiO2)
Sandstone
Arenite (primarily composed of SiO2)
Sandstone (with carbonaceous plant fragments)
Arenite (composed primarily of SiO2)
Shale
Fissile Siliciclastic Sedimentary Rock
Diorite (Salt and Pepper Rock)
Diorite
Orange Calcite
Calcite (Calcium Carbonate, CaCO3)
Chert
Silicon dioxide (SiO2)
Granite
Granite
Granite
Granite (Felsic Plutonic Rock)
Quartz (on matrix)
Quartz (Silicon Dioxide, SiO₂)
Quartz with Iron Stains
Quartz (SiO2) with iron oxide/hydroxide staining
Aventurine (likely Green Aventurine)
Silicon Dioxide (SiO2) with mineral inclusions
Schist
Schist (various mineralogical compositions including mica, chlorite, talc, etc.)
Quartz (Float/Abraded)
Quartz (SiO₂)
Pyrite
Iron Pyrite (FeS2)
Mixed Tumbled Gemstones and River Rocks
Mixed Decorative Stones (predominantly Silicon Dioxide - SiO2 variants)
Sodalite
Sodalite (Na8(Al6Si6O24)Cl2)
Sandstone (Ferruginous)
Arenite (Fe-oxide cemented)
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Iron Oxide cement)
Shale
Fissile Mudstone
Sandstone (Ferruginous)
Clastic Sedimentary Rock (SiO2 with Fe2O3/FeOOH cement)
Felsic Igneous Rock (likely Rhyolite or weathered Granite)
Felsic Volcanic/Plutonic Rock
Gastropod Steinkern (Internal Mold Fossil)
Gastropoda (Class); Internal mold or 'Steinkern' composed of Calcium Carbonate (CaCO3) or Sedimentary matrix
Yellow Chalcedony
Chalcedony (a cryptocrystalline variety of Quartz, SiO₂)
Smoky Quartz
SiO2 (Silicon Dioxide)
Calcite
Calcite (CaCO₃, Calcium Carbonate)
Amethyst
Quartz (SiO2) variety
Marble
Marbles are primarily composed of calcite (calcium carbonate, CaCO3) or dolomite (calcium magnesium carbonate, CaMg(CO3)2).
Basalt
Basalt (Mafic volcanic rock)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Sodalite
Sodalite (Na8(Al6Si6O24)Cl2)
Hypersthene (or Enstatite/Ferrosilite)
Orthopyroxene series (Mg,Fe)SiO3 - specifically, historically hypersthene (intermediate member) now referred to as Enstatite (Mg-rich) or Ferrosilite (Fe-rich)
Natural Gemstone Cabochons (Ruby, Moonstone, Emerald, Citrine)
Ruby (Al2O3:Cr), Moonstone (KAlSi3O8), Emerald (Be3Al2(SiO3)6:Cr), Citrine (SiO2)
Porphyry (likely Porphyritic Andesite or Basalt)
Porphyritic Igneous Rock
Basalt
Mafic Igneous Rock
Basalt
Mafic Igneous Rock
Basalt
Mafic Igneous Basalt
Basalt
Mafic Igneous Rock
Basalt
Mafic Igneous Rock
Basalt River Stone
Basaltic Igneous Rock
General Rock and Mineral Collection (Center: Angelite / Blue Anhydrite)
Anhydrite (Calcium Sulfate, CaSO4)