This is an old classic from the ancient English mining districts, with absolutely jet-black, lustrous, sharp crystals of sphalerite that are so sharp they look more like cassiterite. Five significant jet-black crystals of Sphalerite, splendent and euhedral, are well distributed across a matrix consisting of hundreds of small, lustrous Sphalerites. The matrix is also decorated with perhaps a hundred tan rhombs of what is likely Calcite. The largest of the Sphalerites is an impressive 2.5 cm across. A visually attractive old-timer, in excellent condition! The label is from the former Bally museum in Switzerland.