River Pebble (Brecciated Chert/Siltstone)
Silicon Dioxide (SiO2) with mineral inclusions
sedimentary
Category
Mineral (Tectosilicate)
Browse mineral (tectosilicate) specimens identified by the Rock Identifier community.
Black Jasper
Black Jasper (Silicate mineral - SiO2)
sedimentary
Goldstone
Not a natural mineral or rock. It is an ornamental glass.
Manufactured Glass (Simulant)
Quartzite
Quartzite (Primary mineral: Quartz, SiO2)
metamorphic
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic volcanic rock with secondary mineral fillings)
igneous
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
mineral
Sandstone (Quartz-rich)
Arenite (SiO2 based clastic rock)
sedimentary
Vesicular Basalt
Vesicular Basalt (rich in silicate minerals mostly Plagioclase and Pyroxene)
igneous
Schist
Mica Schist
metamorphic
Schist (with Iron Oxide)
Mica Schist
metamorphic
Epidote in Matrix (likely Amphibolite or Gneiss)
Epidote (Ca2(Al2,Fe)(SiO4)(Si2O7)O(OH)) in Metamorphic Matrix
metamorphic
Pegmatite (with smoky quartz and tourmaline/biotite)
Pegmatitic Granite
igneous
Man-made Slag (Industrial Byproduct)
Anthropogenic Glassy Residue
not a natural rock
Cinnabar
Mercury(II) sulfide (HgS)
mineral
Sandstone
Arenite (primarily SiO2)
sedimentary
Amygdaloidal Rhyolite (often called Lake Superior Agate relative)
Rhyolite with Calcite/Quartz amygdules (SiO2 and secondary minerals)
igneous
Marble
Metamorphosed Limestone (main mineral: Calcite, CaCO3)
metamorphic
Green Aventurine
Silicon Dioxide (SiO2) with Fuchsite inclusions
metamorphic
Calamites (Fossil)
Calamites sp. (Tracheophyta, Equisetopsida)
sedimentary
Granite Pegmatite with Tourmaline and Muscovite
Pegmatite (Feldspar: KAlSi3O8, Quartz: SiO2, Schorl: NaFe2+3Al6(Si6O18)(BO3)3(OH)3(OH))
igneous
Sandstone
Arenite
sedimentary
Quartzite with inclusions
Metamorphosed Quartz-rich Rock (SiO2)
metamorphic
Manganese Oxide Crust on Limestone
Manganese Oxides (e.g., Pyrolusite MnO2 or Romanechite) on CaCO3
sedimentary
Lapis Lazuli
Lapis lazuli (a rock primarily composed of Lazurite, (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)
metamorphic
Note regarding image quality
Indeterminate
Pyrite on Limestone
Iron Disulfide (FeS2) in Calcium Carbonate (CaCO3) matrix
sedimentary (matrix) / mineral (inclusion)
Quartzite with inclusions
Metamorphic Rock (Mainly SiO2)
metamorphic
Granite
Granite (a common name for a felsic intrusive igneous rock)
Igneous Rock
Ferrochrome Slag
Anthropogenic slag (Fe-Cr alloy waste)
industrial byproduct
Gneiss (specifically Micaceous Gneiss)
Gneiss (High-grade Regional Metamorphic Rock)
metamorphic
Gneiss (with Mica and Quartz)
Gneissic Metamorphic Rock
metamorphic
Pyrite in Quartz
Iron Sulfide (FeS2) in Silicon Dioxide (SiO2)
mineral
Turquoise
Turquoise (Hydrated phosphate of copper and aluminium), CuAl6(PO4)4(OH)8·4H2O
mineral
Milky Quartz with Iron Staining
Quartz (Silicon Dioxide, SiO2)
mineral
Limonite/Goethite Gossan
FeO(OH)·nH2O (Hydrated iron oxide)
mineral
Magnetite
Iron(II,III) oxide (Fe3O4)
mineral
Rough Ruby
Corundum (Al2O3 with Chromium impurities)
mineral
Manganese-coated Sandstone
Clastic sedimentary rock with Manganese Oxide (often Pyrolusite or Psilomelane)
sedimentary
Bornite (Peacock Ore)
Bornite (Cu5FeS4)
mineral
Fluorite
Fluoride (Calcium Fluoride - CaF2)
mineral
Ferruginous Sandstone (River Pebble)
Clastic Sedimentary Rock (primarily SiO2 with Fe2O3 cement)
sedimentary
Granite
Granite (High-silica plutonic rock)
Igneous