NEW YORK ( TheStreet) -- Solitario Exploration & Royalty ( XPL), Mines Management ( MGN) and Silver Wheaton ( SLW) topped the gainers' list last week; Teck Resources ( TCK), Southern Copper ( SCCO) and Rio Tinto ( RIO) were in the losers' list.Solitario Exploration & Royalty was the top advancer last week, gaining around 26.1%. On February 17, the stock saw unusual market activity with increased trading volume. Silver stocks dominated the winners' list as the white metal's COMEX spot delivery rose 6.8% last week. Mines Management and Silver Wheaton surged 15.7%, and 14.5%, respectively, leading the pack of silver producers. Compania de Minas Buenaventura ( BVN) jumped 12.0%. The stock hit six-week highs in Lima last week, trading on investors' speculation that the earnings report scheduled for Feb. 24 will reflect gains from subsidiaries, Bloomberg reports. Among other silver producers, Pan American Silver ( PAAS), Hecla Mining ( HL), Coeur d'Alene Mines ( CDE), Mag Silver ( MVG), Endeavour Silver ( EXK) and Silver Standard Resources ( SSRI) posted 11.2%, 10.9%, 10.0%, 9.9%, 8.1% and 8.0% gains, respectively. Cliffs Natural Resources ( CLF) advanced 10.3%, after reporting 2010 fourth quarter adjusted earnings per share at $2.82 vs. estimates of $2.22. Longbow raised its price target on the stock to $135 from $100, reflecting a 39.8% upside. Gold Fields ( GFI) rose 9.2%, riding on its results for the second quarter ended December 31, 2010. Earnings ex-items were $211 million, in comparison to $135 million reported in the year-ago period. Meanwhile, for 2011, the company plans to increase its output by around 5.7%. Citi raised its price target to 100 Rand from 95 Rand, while Morgan Stanley raised its target to 125 Rand from 116 Rand. AK Steel ( AKS) gained around 8.8%. During the week, the company announced increasing stainless steel prices by 4 cents per pound. Meanwhile, U.S. Steel ( X) advanced 5.0% after Goldman Sachs upgraded the stock to buy from neutral and raised the price target to $75 from $61, based on U.S. Steel's leverage on rising steel prices. In addition, Goldman increased EPS estimates to $3.50 from $2.50 for 2011, $6.00 from $5.00 for 2012, and $6.25 from $5.50 for 2011. Other steel producers like Steel Dynamics ( STLD), Schnitzer Steel Industries ( SCHN) and Ternium ( TX) were up 7.4%, 5.7% and 4.7%, respectively. Barrick Gold ( ABX) piled 8.2% after reporting 2010 fourth quarter adjusted earnings per share at 95 cents vs. estimates of 86 cents. Meanwhile, net income quadrupled to $896 million from $215 million reported a year earlier.