Dumortierite, also known as Blue Denim Stone, is an aluminum borate silicate. Dumortierite varies in mediums to midnight blue colors caused by the presence of manganese, iron and zinc. Dumortierite aids mental capabilities in overcoming difficult situations. Dumortierite promotes positive thinking and mental discipline, especially in regard to learning new things. Dumortierite helps open the Third Eye and Throat Chakras.