I think the chance that Máxima has a black person in her ancestry is greater than the chance that she descends from an Inca Emperor...
But a closer look to the ancestry learns:
In the paternal line :
- her father Jorge Zorreguieta was a landowner, a government minister and president of employers unions
- her grandfather Juan Antonio Zorreguieta was a landowner and a banker
- her great-grandfather Amadeo Zorreguieta was a landowner, a mayor and a government minister
- her great-grandfather Oreste Stefanini was a maritime enterpreneur
- her great-great-grandfather Mariano Zorreguieta was a landowner, a government minister, member and president of the senate
- Etc.
In the maternal line:
- her grandfather Jorge Horacio Cerruti was a landowner, a medical doctor and a surgeon
- her great-grandfather Santiago Cerruti was a landowner, a medical doctor and a surgeon
- her great-grandfather Domingo Carricart was a landowner, a banker and a mayor
- her great-great-grandfather Santiago Cerruti (the Cerruti whom emigrated to Argentina) was a marine enterpreneur
- her great-great-grandfather Bernardo Carricart (the Carricart whom emigrated to Argentina) was a veterinarian doctor
- Etc.
So all by all, Máxima's ancestors seems to have belonged more to the
Haves than to the
Have-nots in society. Back then Argentine society was very class-conscious, so I doubt a marriage with someone "below the standing" (mayors, bankers, ministers, surgeons) would have been acceptable...