Indigo Gabbro is a relatively new crystal mined in Madagascar and in various locations in Alaska. It has an amazing array of colors from light indigo purple to black. “Gabbro” refers to a large group of dark, coarse-grained mafic, or igneous rock, formed of silicate [SiO2, or quartz] that is rich in magnesium and iron. It has a chemical equivalent to basalt, but with decidedly different energies. Gabbro is an essential part of the oceanic crust.