... Block Each face with different size of the hemispheres. Jewelry Tool Steel Dapping BlockEach face with different size of the hemispheres ... . Six working surfaces with 21 various sized depressions.It features 17 machined half-sphere depressions: 3.2, 4.8, 6.4 ... , 7.9, 11.1, 12.7, 14.3, 15.9, 17.5, 19.1, 20.6, 22.2, 25.4, 28 ... , and 34.9mm(1/8” to 1-1/3”). Jewelry Tool Steel Dapping Block