an artist in metal, was the maker of the celebrated iron helmet of Alexander, which glittered like polished silver, and the neckchain of which was studded with precious stones. (Plut. Alex. 32.) Plutarch does not expressly tell us that the helmet was chased, but it can hardly be supposed that its magnificence consisted only in its polish; and therefore we do not hesitate to place Theophilus among the most distinguished of the Grecian caelatores. (Comp. Dict. of Antiq. s. v. Caelatura, 2d ed.; R. Rochette, Lettre à M. Schorn, p. 418, 2d ed.)
[P.S]A Dictionary of Greek and Roman biography and mythology
Smith, William
A Dictionary of Greek and Roman biography and mythology. William Smith, LLD, ed. 1890