Valentin van Hassel (1852-1938) begins his career as a private practitioner in 1877 in Pâturages, before starting to work in the region’s mines. Concerned with the fate of the workers, he participates to their education through the publication of a patois literature, and will work to create a healthcare centre for miners. Involved in politics, he will militate in the liberal party but will not obtain a political mandate. The interest of his archives lies in his literary production and his privileged relations with some Belgian authors, including Théo Hannon. His involvement in politics shows the intricacies of the local liberal activism. In his papers, the patois culture holds a key place despite its decline. His involvement in local collieries proves very interesting on the relations of strengths imposed by the industry on the workforce.