Green’s Dictionary of Slang

1. Aus. a very light-complexioned mixed-race person.

1913

Sport (Adelaide) 15 Mar. 12/1: They Say [...] That Ranji is not dark enough to be called Nigger and is not white enough to be called Snowflake, so they have christened him Chocolates.

2. (US black) a white; or a black person who apes whites; also attrib.

1945		D. Burley N.Y. Amsterdam News 27 Jan. 12A: A snowflake chick was on this end [of a telephone line] talking [...] ‘I wouldn’t like to be in your shoes if that Florida operator know who pretty, white, blonde and blue-eyed I am’.
1972		B. Rodgers Queens’ Vernacular 63: black man [...] snowflake.
1977		L. Heinemann Close Quarters (1987) 225: One a us brothas gotta be the Crazy Nigga roun’ here since Snowflake Surtees — that chicken-shit fucken shine — took off.
1986		R. Hewitt White Talk Black Talk 237: It’s just a good laugh, like I go, ‘alright, rassman?’ an’ he’ll go ‘alright, snowflake?’.
1999		‘Master Pimp’ Pimp’s Rap 108: Sampson, the bondsman, could give me the rundown on this snowflake whore.

3. (N.Z. prison, also Snow White) a white person.

2001

D. Looser Boobslang [U. Canterbury D.Phil. thesis] 172/1: Snow White (also snowflake) n. a P?keh?