Granite
Phaneritic Plutonic Igneous Rock (primarily composed of quartz, alkali feldspar, and plagioclase)
Category
Browse industrial byproduct (anthropogenic rock like material) specimens identified by the Rock Identifier community.
Granite
Phaneritic Plutonic Igneous Rock (primarily composed of quartz, alkali feldspar, and plagioclase)
Granitic Pegmatite
Granite Pegmatite (typically containing Quartz SiO2, Feldspar KAlSi3O8, and Muscovite)
Basalt with Magnetite
Crystalline Basalt (Primarily Plagioclase and Pyroxene) with Magnetite (Fe3O4)
Green Sea Glass
Amorphous Silica (man-made glass), SiO2 + additive metal oxides
Quartzite
Quartzite (SiO2)
River Rocks (Polished River Pebbles)
Stream-rounded clastic sediments
Dendritic Agate
Dendritic Agate (Silicon Dioxide with Manganese or Iron Oxide inclusions, SiO2)
Quartz with mica and feldspar (Pegmatite fragment)
Granitic Pegmatite (composed mainly of SiO2 with KAlSi3O8)
Chalcedony
Silicon Dioxide (SiO₂)
Quartz Geode
Silicon Dioxide (SiO2) within a geode
Chert (Flint)
Microcrystalline Quartz (SiO2)
Magnetite (Lodestone)
Iron(II,III) oxide (Fe3O4)
Quartz (Milky Quartz / Greenish Quartz)
SiO2 (Silicon Dioxide)
Chert / Flint Nodule
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Basalt
Basalt
Serpentinite
Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)2-3(Si, Al, Fe)2O5(OH)4
Banded Chert (Flint)
Microcrystalline Quartz (SiO2)
Sandstone
Arenite (SiO2 based)
Biotite (Black Mica)
Biotite (K(Mg,Fe)3AlSi3O10(OH)2)
Quartzite
Quartzite (SiO2)
Almandine Garnet
Almandine, Fe3Al2(SiO4)3
Chert (variations include Flint or Jasper)
Silicon Dioxide (SiO2)
Dyed Agate
Silicon Dioxide (SiO2) - variety Chalcedony
Granite
Granite (Phaneritic intrusive igneous rock)
Almandine Garnet
Almandine - Fe3Al2(SiO4)3
Basalt
Basalt
Bumble Bee Jasper
Calcite-bearing Volcanic Tuff (not a true Jasper)
Hypersthene
(Mg,Fe)SiO3 - Enstatite-Ferrosilite series
Chert (Chalcedony/Common Opal)
Microcrystalline Quartz (SiO2)
Quartzite
Quartzite (composed primarily of SiO2)
Fossil Coral
Coral Limestone (a type of biogenic sedimentary rock)
Limestone with fossil crinoid stems
Calcium Carbonate (CaCO3) containing Crinoidea fossils
Amethyst and Limestone
Amethyst (SiO2 - Silicon Dioxide) and Limestone (CaCO3 - Calcium Carbonate)
Quartz Geode (partially opened)
Silicon Dioxide (SiO2) with iron staining
Chert (Flint)
Silicon Dioxide (SiO2)
Agate
Chalcedony (SiO2)
Marble
Recrystallized Calcite (CaCO3)
Quartz (Milky or Iron-Stained)
Silicon Dioxide (SiO2)
Chert
Microcrystalline Quartz (SiO2)
Garnet Schist
Almandine-Garnet Mica Schist
Garnet Schist
Almandine Garnet-bearing Mica Schist
Petrified Wood
Silicified Wood (SiO2)