 The U.S.-listed shares of Yamana Gold Inc. AUY, 19.85 YRI, 16.49 shot up 21.2 in morning trading Friday, after the Canada-based gold, silver and copper miner received by buyout bid from Pan American Silver Corp. PAAS, -3.41 PAAS, 1.00 and Agnico Eagle Ltd. AEM, 0.71 AEM, 3.49 that values Yamanas stock at a 23.0 premium. 