SHANGHAI, Aug 21 (Reuters) - China's major stock indexes opened down on Friday amid global market weakness and concerns over China's economy.
Investors had expected another day of high volatility, as stock index futures for August delivery will be settled on Friday, marking a showdown between bulls and bears on the contracts.
The CSI300 index fell 1.0 percent to 3,722.81 points at 1:34 GMT, while the Shanghai Composite Index lost 1.3 percent to 3,615.64 points.
China CSI300 stock index futures for August fell 0.7 percent, to 3,736.2, 13.40 points above the current value of the underlying index.
The Hang Seng index in Hong Kong was down 2.0 percent, to 22,310.86 points. (Reporting by Samuel Shen and Pete Sweeney; Editing by Eric Meijer)