Indigo Gabbro is a plutonic igneous rock — meaning it crystallized slowly underground from magma is also refered to as Mystic Merlinite.

It is not a single mineral but a mixture of minerals, dominated by plagioclase feldspar and pyroxenes, with accessory amphiboles, olivine, and minor opaque oxides.

The name “Indigo” refers to its striking mottled appearance of black, dark gray, and purple-indigo patches mixed with lighter gray or white feldspar.

Indigo Gabbro in the gem/lapidary market is mostly quarried in Madagascar, though gabbros are widespread worldwide, it is popular among collectors because of its unusual purple-black coloration.