Gold and silver prices lost luster Thursday as the dollar rallied and the euro tumbled on news that Spain may need as much as 62 billion euros ($78 billion) extra to bailout its troubled banks. In afternoon trade, SPDR Gold Shares (GLD) fell 2.6% to a three-week low. IShares Silver Trust (SLV) dropped 4.29%. The miners crashed even harder. Market Vectors Gold Miners ETF (GDX) plunged 4.29%, while Global X Silver Miners ETF (SIL) collapsed 6.08%.