According to the Annals the “Minas do Pintor” which exploited vertical veins through a single well, being still done the treatment for the arsenic production. The soil is composed of schist and limestone. The mine had only one entrance, by the well, but had an emergency exit in the first gallery. The well has 204 meters deep and extends to 8 galleries. Between 1881 and 1891 the mine underwent several enlargements. In 1914, in Ossela, next to the Castro de Ossela was built a power station that was abandoned in the 60s. Despite being a relatively new industrial area, its regional economic importance accentuates the mining extraction techniques.
Location: Oliveira de Azeméis
