Green’s Dictionary of Slang

1. (W.I.) sixpence (post-1969 value 5 cents).

1822		S.A. Mathews Willshire Squeeze 14: Joes and doubloons from purse / Were tumbled out.
1833		T. Foulks Eighteen Months in Jamaica 32: The higher grade will bet a two dollar piece, a pistole, a half joe.
1863		G.A. Sala Strange Adventures of Captain Dangerous 157: The unhappy creature, who had probably sold my Tobacco-stopper for a few joes [...] positively denied that I had given her anything beyond the half-dollar.
1869		H.G. Murray ‘Tom Kittle’s Wake’ in D’Costa & Lalla Voices in Exile (1989) 95: Several doubloons, some ‘half-joes,’ Spanish dollars and ‘pistereen bits’.
1873		C. Rampini Letters from Jamaica 95: The negro nomenclature of coins is as follows: – [...] Joe, sixpence.

2. (N.Z.) one penny.

1984

Partridge DSUE (8th edn) 623/2: –1935.