China\'s stock index futures closed mixed on Friday, with the contract for August 2013, the most actively traded, up 0.2 percent from the previous trading day to 2,330.0 points. The September 2013 contract lost 1.85 percent to finish at 2,286.2. The December 2013 contract moved down 1.68 percent to 2,298.8 points, while the March 2014 contract declined 1.69 percent to end at 2,307.6 points. The stock-index contracts, agreements to buy or sell the Hushen 300 Index at a preset value on an agreed date, are designed to allow investors to bet on and profit from either gains or declines in the market. The index futures was launched at the China Financial Futures Exchange (CFFEX) and started trading from April 16, 2010. The CFFEX has set the base value for all the four contracts at 3,399 points.