The Magnesite Mines Curiosity · Borobia, Moncayo, Soria Image of Borobia, not of the place itself. The municipality works deposits of magnesite, the magnesium carbonate used in refractories and in industry; beside one of the hermitages there were also old iron ore workings. Photo: Diego Delso (CC BY-SA 4.0) What to see and do in Borobia