The cotton market was shut Thursday for Thanksgiving. Trading ended an hour earlier than the normal closing time of 2 p.m. EST (1900 GMT) on Friday. The key March cotton futures shed 0.04 cent to end at 90.87 cents per lb, after trading between 90.01 and 91.89 cents. For the week, the market was down almost 2.5 percent. Total volume traded Friday was a little over 6,500 lots, almost three quarters below the 30-day norm, preliminary Thomson Reuters data showed. "It's very thin," said Sharon Johnson, senior cotton analyst at commodity brokerage Penson Futures in Atlanta. US stocks were up but the market was still seemingly headed for its worst week in two months on crimped holiday trading and fears that Europe's debt crisis lacked a unified response. China, the world's top producer and consumer of cotton, was again the biggest buyer of US cotton in the US Agriculture Department's weekly export sales report -- which was released on Friday due to Thursday's Thanksgiving holiday. China bought 757,700 running bales (RBs, 500-lbs each), bringing total purchases over the last three weeks to over 2.3 million RBs of cotton. "Cotton remained weak because aside from China, there are no other buyers of note in the market," a dealer said. Open interest in the cotton market, usually taken as an indicator of investor exposure in the market, stood at 136,858 lots as of Nov 23, from the prior session's tally of 137,106 lots, exchange data showed. Total volume traded Wednesday in the market reached 14,825 lots, from the previous tally of 24,770 lots, ICE futures US data said.