SHANGHAI, Oct 12 (Reuters) - China's major indexes were mixed on Thursday, as gains in financial stocks offset losses in resources firms after Beijing vowed to curb pollution throughout winter.
The blue-chip CSI300 index rose 0.3 percent, to 3,912.95 points, while the Shanghai Composite Index shed 0.1 percent to 3,386.10 points.
Resources firms continued to weigh, with energy stocks , in particular coal producers, sliding, after the country's top coal producing region vowed to cut concentrations of hazardous airborne particles by 40 percent over the winter months.
Shares in top coke producer Shanxi Coking dived 7.6 percent to six-week lows, after it planned to slash output of coke as part of Beijing's campaign against air pollution, especially over the winter.
However, market moves remained largely measured ahead of a key party congress, with heavyweight financial sector led the gains with a 0.5 percent gain.
Wu Kan, head of equity trading at Shanshan Finance, expected little market volatility before and during China's 19th Communist Party Congress, which will open on Oct. 18.
China's securities regulators have said maintaining market stability is a major political task during the period.
"There's a lot of expectation that the government will accelerate state-owned enterprise (SOE) reforms," Wu said, explaining why defence-related stocks, most of which are state-owned, surged on Thursday.
The jump in the sector, which includes Avic Aviation High-Technology Co and China Spacesat Co , also appeared to be triggered by news that a U.S. Navy destroyer sailed near islands claimed by China in the South China Sea on Tuesday. (Reporting by Luoyan Liu and John Ruwitch; Editing by Sam Holmes)