The Masua hub was a complex of several mining operations in the Sulcis area, a region of Sardinia rich in coal, sulphur, barium, zinc, lead, silver and other metals. Extraction began in 1600, but became economically relevant only in the early 1900s when the mining business in the whole region experienced a quick expansion. The extraction, especially of the coal caves, was operated on a low-technology basis until the early 20th century. Since the late 1800s metal-gathering enjoyed more modern techniques, as it was controlled mostly by rich north-European corporations more willing to commit money in improving the mining efficiency. In 1922, the Masua mines were acquired by the Belgian Vieille Montagne Company, and exploitation increased with the growing need for zinc and lead for reconstruction after World War I as well as because of technological advance in steel alloys.