Abstract

Having conquered Volterra in 1472, Florence obtained the right to exploit its alum deposits, set up a mining centre alongside the papal one of Tolfa, and attempted to make the Florentine wool industry autonomous. While Medici interests in this sense are well known, this article, following the commercial lines of Volterra’s alum, formulates new hypotheses on the commercial, political and diplomatic implications linked, at an international level, to that mineral’s circulation in the late Middle Ages. The lawsuit over compensation brought against Florence by the Sienese Capacci brothers, retraced through analysis of the documentation in the State Archives of Florence, opens original perspectives on the issue of the exploitation and circulation of Volterra alum.