Axinite is a brown to violet-brown, or reddish-brown bladed group of minerals composed of calcium aluminium boro - silicate, (Ca,Fe,Mn)3Al2BO3Si4O12OH. Axinite is pyroelectric and piezoelectric. The axinite group includes: Axinite is sometimes used as a gemstone. [8] Wikimedia Commons has media related to Axinite. ^ Warr, L.N. (2021).