This dravite tourmaline is from the Pomba Pit in Serra das Egus, Brumado, Bahia, Brazil. This mine is a commercial producer of magnesite and talc however dravite and other accessory minerals, including emeralds are found there. The mine owners enforce a ban on mineral collecting and that includes the miners that work there. Dravite is in the Tourmaline Group of minerals and it is a silicate that contains the elements Na, Mg, Al, Si, O, B and H. These crystals are thick and opaque. They are dark brown to black in appearence and they have a greasy luster. The piece is good on all sides and it measure 1 1/16 x 5/8 x 11/16 inches or 27 x 16 x 18 mm.