Green’s Dictionary of Slang

(Aus.) a general derog. name used in various combs., e.g. Kimberley mutton, roast goat; Kimberley oyster, a meat fritter.

1939		I. Idriess Works 238: I’ve killed a goat, so you can get some of that into you. Kimberley mutton isn't half bad .
1945		T. Ronan Strangers on the Ophir 39: A meat fritter known in the Kimberleys as a ‘Burdekin Duck’, and on the Burdekin as a ‘Kimberley Oyster’ [GAW4].
1953		C.C. Rees Spinifex Walkabout 119: You’ve tasted goat, of course — they call it Kimberley mutton up here.
1954		Bulletin 25 Aug. 12: W.A.’s Government botanist, C. A. Gardiner, has established that the Kimberley (walkabout) horse disease is caused by the animals eating the wedge-leaved rattlepod.
1959		J. Cleary Back of Sunset 167: Steve [...] beginning to carve the roast goat, Kimberley mutton, as it was called.