Stone Point Chisel: a Point for Marble and Granite, Forged from Square Steel (Holford, 1907)

The point is the hard-stone carver's roughing tool, struck with a hammer to break stone away in furrows. Frederick Holford's 20th Century Toolsmith (1907) gives the granite cutter's point: drawn down very thin at the extreme end but with a very short taper, best forged from 7/8-inch square steel because a square point sits on the stone and does not twist in the hand. It is hardened no more than 1/2 inch back and dipped at least an inch deep so the temper draws very slowly; for granite to a dark straw, for marble a little harder, to a very light straw. Holford gives no length and no carbon content for these tools; those are unknown here. Source: F. J. Holford, The 20th Century Toolsmith and Steelworker (1907), pp. 122-123, 130 and p. 21 (the hardening bath). Picture: his Fig. 62 (point above, chisel below).