You forgot about Brown and the less common Orange. Prominent DC politicians include Mayor Vincent Gray, his top aide Lorraine Green, DC Councilman Vincent Orange, and DC Council Chairman Kwame Brown (not the former Wizards center): all are black, but none are surnamed so.
The 1983 Kansas City Royals had Frank White, who is black, Bud Black, who is white, and Vida Blue, whose skin color is more of a dark purple.
Very colorful city. ;d
I almost forgot Green too but I was fixated on the rather unusual Blue cause I was thinking of Dan Blue.
I can’t think of a famous person with the surname Black that isn’t White.