Ebony
One of the most intensely black woods known, the density of ebony is so high that it sinks in water but means that it can be polished to a glossy finish. Perhaps most famous for its use as the black keys on pianos, the Ebony we are using at the moment was given to us by a local wood turner.
In the last slides you can see examples of ebony inlaid in an R1C 5mm titanium ring and in a silver set of C2AL cufflinks and R38 11mm ring.