The top share index has won back most of yesterday's losses, with a rally in the mining sector driving the gains.Fresnillo leads the large cap miners higher. The Mexican miner's silver production slipped slightly in the quarter to 31 March, but expanded capacity at its Soledad-Dipolos mine helped lift gold production by 13.3% to 96,407 ounces. Fresnillo's chief executive Jaime Lomelin said the company is on track to produce 44m ounces of silver over 2011.Elsewhere in mining, Rio Tinto said first quarter production in Australia was hit by the extreme weather in the region but most of its operations are now recovering and benefiting from strong prices. Global iron ore production of 42m tonnes attributable was down 3% on the first quarter of 2010 and down 16% on the fourth quarter of 2010. Operations in the Pilbara were disrupted by three tropical cyclones and widespread flooding.Shares in ARM Holdings are in demand today, helped by some positive comment from the broker ING, which expects ARM to meet its guidance.Teen outfitter JD Sports Fashion hiked its dividend by about 30% after reporting a sharp rise in profits but said it is "extremely cautious" on the outlook. The sports-themed fashion retailer posted a pre-tax profit of £78.6m in the year to 29 January, up from £61.4m the previous year, on revenues that rose to £883.7m from £769.8m. The full-year dividend is upped to 23p from 18p.Oil and gas firm Tullow Oil has had another success off the coast of Ghana, with the Tweneboa-4 appraisal well in the Deepwater Tano licence encountering gas condensate in good quality sandstone reservoirs. The company added that it is resuming its exploration and appraisal campaign in Uganda. The company expects to have a five-rig drill-out campaign on the go in the second half of this year.Design and engineering consultancy WS Atkins said it expects full year results to be ahead of market expectations after a strong performance at its Middle East business. The group, which is the official engineering design services provider for the London 2012 Games, said overall it had traded well through the fourth quarter. Its UK business continues to perform in line with expectations despite challenging market conditions. Strong growth overseas helped the internet fashion retailer ASOS maintain its upward momentum in the fourth quarter. The firm, which sells clothes inspired by trendy celebrities (the name stands for 'As Seen on Screen') saw year-on-year sales growth of 70% during the quarter, with UK's revenues up 24% to £44.9m and the international division's soaring by 161% to £48.4m.Smaller gold miners are also in focus today. Shares in Ireland's Conroy Gold were shining after it reported positive results from a drilling programme at its Clontibret gold project. "The drill hole intersected 1.25 metres of 2.29 g/t gold from 84 metres and 10.15 metres of 4.38 g/t from 132.4 metres including 2 metres at 11.24 g/t and 1.4 metres at 7.92 g/t," the company said. But Condor Resources was on the descent on Wednesday after releasing a mineral resource estimate for its La India and Espinito concessions in Nicaragua. FTSE 100 - RisersARM Holdings (ARM) 583.50p +4.20%GKN (GKN) 204.00p +3.76%G4S (GFS) 268.90p +2.91%Reckitt Benckiser Group (RB.) 3,317.00p +2.69%Hargreaves Lansdown (HL.) 622.00p +2.39%Sage Group (SGE) 274.70p +2.39%Tesco (TSCO) 406.75p +2.19%Serco Group (SRP) 553.50p +2.12%Xstrata (XTA) 1,495.50p +2.05%Admiral Group (ADM) 1,640.00p +1.99%FTSE 100 - FallersOld Mutual (OML) 141.40p -2.35%IMI (IMI) 988.50p -2.23%Capita Group (CPI) 705.00p -1.33%TUI Travel (TT.) 230.40p -0.86%Amec (AMEC) 1,159.00p -0.86%Lonmin (LMI) 1,680.00p -0.47%John Wood Group (WG.) 662.50p -0.38%BT Group (BT.A) 188.90p -0.21%Aviva (AV.) 442.90p -0.18%ITV (ITV) 75.20p -0.13%FTSE 250 - RisersAtkins (WS) (ATK) 742.50p +7.84%Brown (N.) Group (BWNG) 275.70p +3.65%Genus (GNS) 973.00p +3.46%Supergroup (SGP) 1,407.00p +3.30%Debenhams (DEB) 66.95p +3.16%Barratt Developments (BDEV) 104.70p +3.05%Carpetright (CPR) 654.00p +2.83%Hunting (HTG) 803.50p +2.68%Pace (PIC) 158.90p +2.58%William Hill (WMH) 184.90p +2.55%FTSE 250 - FallersJupiter Fund Management (JUP) 279.50p -2.95%BBA Aviation (BBA) 199.80p -2.77%Berendsen (BRSN) 480.00p -2.44%JD Sports Fashion (JD.) 879.50p -2.44%COLT Group SA (COLT) 144.00p -2.44%Thomas Cook Group (TCG) 165.70p -2.18%Charter International (CHTR) 749.00p -2.16%Mondi (MNDI) 583.50p -2.02%Filtrona PLC (FLTR) 305.20p -1.86%Cookson Group (CKSN) 649.50p -1.67%