Deal activity gives FTSE 100 miners a boost Miners dug into the FTSE 100"s leaderboard on Thursday after news of a potential $80bn merger in the sector, but a lacklustre reaction to earnings news from the oil sector left the index flat overall. Glencore and Xstrata took the top two places on the leaderboard and their potential union energised their peers, with nine of the top 10 places on the market taken up by members of the sector. Xstrata made the best single gain, up 11 per cent at £12.42. Glencore was in second place, up 4.9% at 451.3p. "A combination of the two companies is likely to provide a boost to the mining sector overall and a bullish signal to the market," said Charles Cooper, an analyst on Oriel Securities" mining team. Glencore was thought to be seeking a zero premium merger, so the big question is whether Xstrata would agree to this. Medical devices maker Smith & Nephew broke into the top 10 with a 2 per cent rise to 626½p after its third-quarter profits recovered, thanks to its cost-cutting programme. Revenue in the period rose 3 per cent to $1.106bn, just less than forecasts, but trading profit beat consensus, reaching $279m, higher than the $271m predicted. Anglo-Dutch consumer products maker Unilever was the worst performer after it warned of a difficult year ahead as it just matched its sales forecasts for 2011. The maker of Hellmann's mayonnaise and Marmite spread reported full-year underlying sales growth of 6.5 per cent, in line with forecasts of 6.4 per cent. Its shares were 3.6 per cent weaker at £20.10. Royal Dutch Shell led the heavily weighted oil companies lower after its fourth-quarter and annual numbers received a cool reception. Stuart Joyner, analyst at Investec, said: "We expect to see material downgrades to the consensus full-year numbers and there is negative risk to the company's capital expenditure outlook given 2011, at $31bn, overshot our forecast by some 10 per cent and reserve replacement was mediocre." Shell also revealed weaker refining margins and low natural gas prices and sounded alarm bells across the sector, prompting it to act as a barrier to overall gains on the FTSE 100. The stock lost 2.7 per cent to £22.63. BP was 1.5 per cent weaker at 475.9p. London's benchmark index was flat at 5,788.38, muted after its biggest gain in a month over the previous session. It remained within sight of last week's intraday high of 5,806.24, its best reading since early August.