Plasticine is also used as synonymous with pliable, flexible etc -
Bob.1955 K. WILLIAMS Diary 14 Dec. (1993) 118, I felt a complete lack of reality about Larry - it was indeed a theatrical Richard, with funny walk, crookback, unformed hands, and a plasticine nose. 1958 Spectator 4 July 12/1 He was so pliant, so plasticine,..so insidiously seeing it all the other chap's way. 1976 Times 28 Jan. 1/3 The Russians..would respect us more if we were led by an iron lady rather than a Plasticine man.
(Plasticine was developed by W. Harbutt in Bath in the mid 1890s (cf. quot. 1897 at sense A.); commercial production began in 1900.)
OED