Re: Mixture of Ebony and Ivory
"Onyx" may be the name you're looking for. Onyx is a mineral which can appear with bands of black and white in it.
If you're looking for a name which may signify the combination of the symbolic "black" and "white", then Onyx would do.
Onyx is also used for making some quite beautiful jewelry, so you have the additional significance of "beauty" which goes with the name.
-- Nanaea