Silver prices plunged on Monday, after having surged 140% this year to fresh record highs. - Spencer Platt/Getty Images Silver prices tumbled Monday, raising alarms about the potential for this year’s stunning rise in the precious metal to run out of steam. The most-active silver contract SI00 SIH26 fell $6,736, or 8.7%, to settle at $70.46 an ounce, according to Dow Jones Market Data. That marked the metal’s biggest one-day dollar drop since Jan. 22, 1980, and followed a fresh record close Friday and it ...