An unusual simile for rust, though of course, once seen, it seems natural. A beech hedge in winter has an intense and often uniform rust colour. 

‘… and the corners were stacked with old weapons that were as rich with rust as a hedge of winter beech.’ 

See a quotation from Zorba the Greek in which it is the rusty old weapons themselves that are the metaphor.

See also our bestellar review of Peake’s book, with a lavishly illustrated quote-mosaic, packed with fine phrasing and fresh metaphors.  

Source: Mervyn Peake, Titus Groan, introduction by Anthony Burgess (London: Vintage Books, 1998), p. 152

Photo credit: Gellinger at pixabay.com