Stone Flat Chisel: the Marble Lettering Tool, Drawn Very Thin (Holford, 1907)

A flat chisel for cutting letters in marble. Frederick Holford's 20th Century Toolsmith (1907) makes marble tools like granite tools, from 7/8-inch octagon steel, but tempers them a little harder, to a very light straw. The lettering tool is drawn out very thin (his Fig. 69); because of that thinness it must be heated with great care, and the last few blows when dressing it are struck on the flat side only, at a very low heat. He gives no edge width, length or carbon content; those are unknown here. Source: F. J. Holford, The 20th Century Toolsmith and Steelworker (1907), p. 130, pp. 122-123 and p. 21 (the hardening bath). Picture: his Fig. 69.