Common Racial Slurs Non-Blacks Use as Codes to Describe Black People

[haele]

24. "Chalky" was sometimes a mid-19th cent./early 20th cent. nickname for AA's.

Often used as a nickname by white people for a black man considered socially acceptable - one a white person could do business with, or one who could pass for white - in the Northeast, notably used by Tammany Hall politicians and some of the 2nd wave Irish immigrants. That's probably which is where the confusion as to "it's heard in Ireland" may have come from.
When I was doing a lot of research for re-enactors back in the day, I came across it several times in contemporary writings.
It was not typically used in the South; and there has one instance I've read about in Texas around 1910 and a couple former slaves with their own businesses out west in the late 1800's who referred to by that nickname.

Haele