Mining stocks tanked on Friday after a series of disappointing manufacturing figures dampened risk appetite.The official Chinese manufacturing purchasing managers' index (PMI) fell from 50.4 to 50.1 in February. While this marked the fifth straight month of expansion (shown by figures above the mid-point of 50), analysts were expecting a slight rise to 50.5.HSBC's own PMI survey for Chinese manufacturing also fell from 52.3 to 50.4 in February, missing the 50.6 estimate."There were suggestions last month that we may see this slide, as an increase in activity was also accompanied by an increase in inventories, so this drop may only be temporary. However, it does suggest that the recovery seen in China is not quite as strong as people had hoped," said Market Analyst Craig Erlam from Alpari this morning.Meanwhile, the Markit/CIPS manufacturing PMI in the UK dropped from a revised 50.5 to 47.9 this month, missing the 51 estimate.FTSE 100 constituents Kazakhmys, EVRAZ, Xstrata, Glencore and Rio Tinto were registering steep losses in afternoon trade.Kazakhmys, which yesterday announced that it would be slashing its dividend to reflect falling profits in 2012, was a heavy faller after Credit Suisse, Bank of America, JPMorgan and Exane BNP Paribas all cut their target prices for the stock.Credit Suisse said that Kazakhmys is "feeling the pinch", having minimal margin insulation from sharp cost increases which puts further pressure on cash flows.Meanwhile, Glencore and Xstrata were also hit after saying that they would likely push back their merger deadline as they continue to await regulatory approval in China.Top performing sectors so far todayPersonal Goods 22,242.71 +1.98%Support Services 5,789.58 +1.94%Travel & Leisure 6,017.34 +1.68%Industrial Transportation 2,725.59 +1.64%Tobacco 38,853.40 +1.63%Bottom performing sectors so far todayIndustrial Metals & Mining 2,677.07 -3.52%Mining 19,354.98 -1.75%Automobiles & Parts 6,310.44 -1.14%Oil Equipment, Services & Distribution 23,189.36 -1.10%Banks 5,045.25 -0.85%BC