The two woods that I work almost exclusively with are African Blackwood and Kingwood, with Kingwodd being my favorite wood of all. The blackwood will come in a range from pure chocolate black color to a lighter black walnut look. The best stuff is in between, having a pure black background with brown swirling grain.
I used to use Ebony until I got my first piece of blackwood, now I try to talk all requests for ebony into blackwood. I found ebony less interesting and less stable. The blackwood is very oily and behaves like it is a member of the rosewoood family. It turns beautifully, carves nicely and comes to a fine lusterous finish by hand or the buffer, and while you are working it gives off an interesting vanilla type flavor that is reminiscent of root beer. I have yet to have a piece of blackwood split out.
Now, the down side. You want to find heartwood and carefully look over any block you buy. Often there will be streaks going through it that are a light color like pine :grumpy: If you like this sort of thing that is fine, but it is always so assymetrical and high contrast that it never looks like much more than a defect to me, but then I guess one gets the same thing with ebony.