I was reading about ebony, some time ago, and the author said that only the "heart wood" of the ebony tree is solid black. Otherwise the wood is brown with strong bands of darker brown. He said that ebony furniture was very popular during the 19th. century because of the influence of Chinese and Japanese art. Most of the ebony used for furniture started out as a more ecomomical local wood that was "ebonized", ie. bleached until nearly white and then dyed black. The black wood on pianos is, supposedly, still made this way today.
John.