The industrial metals and mining sector was unsurprisingly the worst performing category on Friday, as FTSE 250 constituent Talvivaara Mining saw a massive 23.38% of its market value go down the drain.The Finnish nickel and zinc miner announced this morning that chief executive Pekka Perä is to hang up his helmet as soon as the company can find a replacement, as the company goes into cash conservation mode. The company said that, in view of the current volatility and uncertainty in the commodity and financial markets, it has developed a revised operating plan and made the strategic decision to focus on maximising profitability of operations rather than the production volume over the remainder of 2011. The company said that third quarter production suffered from problems with the hydrogen sulphide generators towards the end of the period.Heading the other way was the personal good sector, with Burberry making some strong gains in the afternoon.The for British luxury brand was in demand, a day after Seymour Pierce issued a positive note on the stock, saying that its premium valuation to its peer group is justified."Despite the recent sell off in Burberry shares and the sector generally driven by macro concerns over a potential global slowdown and a hard China landing, we expect Burberry to report strong Q2 trading after a faultless Q1 performance. Focus will be on China's performance and for any evidence that US department stores will cut back wholesale orders for spring/summer 2012," said analyst Kate Calvert. BCTop performing sectors so far todayPersonal Goods 19,728.06 +2.37%Financial Services 4,683.63 +1.27%Construction & Materials 3,229.68 +1.16%Industrial Engineering 6,185.95 +1.15%General Retailers 1,543.16 +1.07%Bottom performing sectors so far todayIndustrial Metals & Mining 4,054.87 -10.91%Food Producers & Processors 5,276.34 -1.87%Beverages 9,652.59 -1.40%Automobiles & Parts 4,215.53 -1.15%Health Care Equipment & Services 3,244.16 -1.03%