These mines are popular knowledge and were discovered after a fire.
They were mentioned by L. Gonçalves ("Sardoal do Passado ao Presente", 1992), who states that he looked on the way down from the chapel of S. Tiago, to Montalegre, almost next to the road, for some deep wells that people say exist and that would have been work of the "Moors".
M. Grácio also recorded the existence of quadrangular vertical galleries, one meter on a side, with a supposed horizontal connection between them.
No associated materials were found.