by my experience of yiddish, and as edited after LIU:
shvartz black (the color)
shvartzer: black person, male; rarely used
shvartzeh : black person, female -- but usually used to mean "housemaid"

At least one recent source states that after some years of debate, the terms are now considered offensive. It is unclear, however, whether this conclusion simply reflects the editor's PC bias.

Yiddish also has a specific term for "black person". However, that term is not suitable for use in an english-speaking society, as its pronunciaton is uncomfortably close to "nigger".