Bannisterite, New South Wales, Australia, Cabinet-Sized SpecimenApprox. Dimensions: 3. 3 in x 1. 8 in x 1. 2 in Approx. Weight: 83 grams A platy, well defined specimen of Bannisterite from the Broken Hill Mine. A rare mineral specimen in rich black and with a unique shape. One prominent plate protrudes at an angle from the top of the piece with the tail end curving down and around on the opposite side.