Miners crushed, Glencore at low as copper tumbles By: CNBC.com News January 14, 2015 at 08:52 AM EST Mining stocks sold off sharply on Wednesday, with Glencore falling to an all-time nadir, after copper plunged to a five-and-a half-year low,. Read More >> Related Stocks: Bhp Billiton Plc ADR Citigroup Glencore International Plc ADR Rio Tinto Plc ADR