Indigo Gabbro is a type of Gabbro—an igneous, intrusive rock formed from magma cooling within the Earth's crust. Characterized by high concentrations of iron and magnesium, Gabbro may also contain chlorite, magnetite, serpentine, or muscovite. Its Mohs Hardness of 6-6.5 results in a brilliant shine when polished, and its unique quartz-feldspar mix is predominantly found in Madagascar.
