Who is Guarionex from A Short Account of the Destruction of the Indies and what is their importance?

Guarionex, who was devoted to the King and Queen of Spain, is described as a dutiful man with a good placid temperament. For years, everyone in his kingdom would send a gourd full of gold to the King and Queen of Spain, though later they sent half gourds because they were running out of gold. The lack of gold, however, wasn't due to a short supply, but rather a lack of knowledge in mining. He later died on a ship bound for Castille.