Stuff. Prunello really means that woollen stuff of which common ecclesiastical gowns used to be made; it was also employed for the uppers of women's boots and shoes; everlasting. A corruption of Brignoles.
Worth makes the man, and want of it the fellow; The rest is all but leather or prunello,
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894