Mining group Kazakhmys rose after announcing that it has been awarded a contract for the construction of a sulphide concentrator at Aktogay, its second major copper growth project, to Non Ferrous China (NFC). The sulphide concentrator contract is the largest item in the capital expenditure budget for Aktogay, it explained, saying it means it is now able to confirm that the total capital cost for the Aktogay project is expected to be in the region of $2.3bn.African Barrick Gold was the top riser, helped in part by a positive note from Numis Securities the previous day.Laird, which earlier this week announced its chief financial officer would step down after 29 years with the company, was also a strong performer.Kier Group fell after going ex-dividend, while Rightmove dropped after Citi cut its target price on the stock from 3,650p to 2,175p.Bank of Georgia declined after the European Bank for Reconstruction and Development revealed that it had sold a 5% interest in the group. It stepped in to lend a hand to the group amid the financial crisis in 2008.Tate & Lyle continued to drop after its target price was cut by a number of brokers, with Societe Generale also opting to lower its rating on the stock, from 'buy' to 'hold'.Materials producer Essentra failed to impress with the news it has agreed to acquire Malaysian security sealing products maker Abric Berhad for around £28m, which is expected to be immediately earnings enhancing.FTSE 250 - RisersAfrican Barrick Gold (ABG) 215.50p +3.76%Kazakhmys (KAZ) 272.10p +2.60%Vedanta Resources (VED) 997.00p +2.31%Laird (LRD) 305.30p +1.77%Stock Spirits Group (STCK) 298.10p +1.74%Rexam (REX) 509.50p +1.70%Poundland Group (PLND) 322.90p +1.67%Playtech (PTEC) 728.50p +1.60%TSB Banking Group (TSB) 279.50p +1.60%Hikma Pharmaceuticals (HIK) 1,656.00p +1.60%FTSE 250 - FallersPace (PIC) 286.50p -4.82%Mitchells & Butlers (MAB) 404.40p -3.48%Bank of Georgia Holdings (BGEO) 2,415.00p -3.32%Kier Group (KIE) 1,650.00p -3.00%Supergroup (SGP) 1,132.00p -2.92%Rightmove (RMV) 2,257.00p -2.92%Alent (ALNT) 345.00p -2.82%Premier Farnell (PFL) 184.80p -2.74%Brewin Dolphin Holdings (BRW) 272.90p -2.47%Restaurant Group (RTN) 640.00p -2.29%