SHANGHAI, May 23 (SMM) – LME zinc prices overnight opened higher at USD 1,910/mt during Asian trading hours, but then plummeted to USD 1,903.3/mt as the US dollar index surged to 81. As Japan's sovereign credit rating was downgraded, investors' concerns grew, pushing down LME zinc prices to USD 1,894.3/mt. The New York Fed's manufacturing index was higher than expected, indicating the manufacturing sector is expanding modestly. As a result, LME zinc prices touched USD 1,910.5/mt and finally closed at USD 1,908.5/mt. Trading volumes decreased by 1,795 lots to 8,530 lots, and total position increased by 103 lots to 267,006 lots. LME zinc prices overnight dipped to USD 1,894.3/mt and finally closed at USD 1,908.5/mt, down USD 1.5/mt.