In 1900, the blast furnaces of Saint-Louis were the only ones in France still producing ferromanganese. As the French steel mills became more and more located in Lorraine, a new production site for ferromanganese was looked for in northern France. At the Channel coast, the recently modernized blast furnaces of Outreau wanted to diversify their fabrications. The two companies came to an agreement and the ferromanganese activity was transferred to this site with great industrial and commercial success. In 1906, a blast furnace moved from Marseille was started up at Outreau as a ferromanganese furnace.