Clearly, the steal of the century folks. This is a Pear Shape stone weighing 55.85 carats and was so named in honor of Amsterdam's 700 anniversary. Then there's the Black Diamond of Bahia. In any case, this stone was discovered in Brazil and was shown at the 1851 Crystal Palace Exposition. But it also comes in dark grays.
Black diamonds are, additionally, often pitted and very difficult to cut.
There is this firm in New York, Tyler-Adam Corp. by name, who can supply one for you. You have but to simply ask.