Reuters: A source of wealth for more than a century as home to one of Europe’s largest copper mines, Serbia’s Bor has struggled for years to attract foreign investment and heal its soiled environment. RTB Bor, the state-owned company that thrived two decades ago as Yugoslavia’s largest copper mine and smelter, fell into disrepair during the 1990s wars, international embargo and mismanagement under President Slobodan Milosevic. “Our technology dates from 1961 and 1971 and we are in dire …