A fine specimen of this rare Barium Calcium Carbonate from the well known Fallowfield Mine, the type locality. The Alstonite specimen displays many spiky pyramidal crystals to 1cm. The lustrous Alstonite crystals are well formed from translucent towards the terminations to a solid milky white at the body of the specimen. The Alstonite has formed around a thin band of mixed Sphalerite and Pyrite apparent on the underside of the specimen.