The International Finance Corp, part of the World Bank, plans to acquire as much as 13 percent of Cia. de Cemento Argos S.A. of Colombia for US$60 million to help Colombia's economy at a time of political violence. The corporation has given Argos, the country's largest cement producer and part of the Medellin-based Grupo Empresarial Antioqueno, an option to reacquire the stake at market prices.