Mumbai, Jan. 22 -- MCX Silver futures tumbled today as local markets witnessed extreme volatility amid a modest selloff in global silver futures. Local markets have been witnessing elevated premiums recently on potential customs duty hike on precious metals in the upcoming Union Budget to be presented on February 1. However, a drop in global prices after the metal hit fresh record highs above $95 per ounce led to a tumble in local futures as well as Silver exchange-traded funds (ETFs). Bullion futures slipped after US President Donald Trump stepped back from his bid to annex Greenland by force, easing safe-haven demand for precious metals. Silver tanked more than 2% in global markets yesterday but managed to edge higher by 1.17% to $93.73 p...