Deep green crystals of dioptase (cameras have a hard time with the color, which is Tsumeb-like in this specimen). The largest crystal measures 1 cm. There are some missing crystals along the sides, but they do not overly detract. This is still a wonderful piece with huge show value and a reat richly crystallized area. the pics stink, so it will be more impressive in person.... 5.1 x 4 x 2.5 cm