Mining stocks were suffering steep losses on Wednesday as metal prices tumbled across the board owing to a stronger dollar and the increased likelihood that the Federal Reserve will soon 'taper' stimulus if economic data continues to improve. Stronger-than-expected US data released on Tuesday - including consumer confidence, home sales, house prices and durable goods - saw the greenback strengthen, causing dollar-denominated commodities such as gold and silver to tumble today.Gold prices were down as much as 4.2% to $1,224.19 an ounce, while silver dropped to a low of $18.385 an ounce, both being their cheapest levels since August 2010.However, losses were trimmed in afternoon trade after US economic growth for the first quarter was revised downwards to 1.8%, well below the initial 2.4% prediction, sparking speculation that the Fed could delay scaling back its asset purchase programme.Nevertheless, mining stocks were still weak with FTSE 100 heavyweights Antofagasta, Anglo American, Fresnillo, Randgold Resources, ENRC and Vedanta all registering hefty falls.FTSE 250 peers Hochschild Mining, Polymetal, EVRAZ and Ferrexpo were also firmly in the red.Top performing sectors so far todayLife Insurance 5,669.52 +2.94%Forestry & Paper 8,590.16 +2.37%Household Goods & Home Construction 10,394.32 +2.23%Chemicals 9,180.46 +2.05%Construction & Materials 3,634.63 +1.88%Bottom performing sectors so far todayIndustrial Metals & Mining 1,183.27 -3.77%Mining 14,398.99 -0.78%Health Care Equipment & Services 4,128.78 -0.20%