Ample supplies of wheat and rice helped to keep the index, which tracks export prices, 10% below its peak in February 2011.

ECONOMIST: Business this week

U.S. economic data due for release Tuesday includes retail sales, the NFIB small business optimism index, import and export prices, the Goldman Sachs and Johnson Redbook retail sales reports, and manufacturing and trade inventories.

FORBES: Comex Gold Weaker on Technical Selling, Firmer U.S. Dollar

U.S. economic data due for release Tuesday includes the NFIB small business index, the weekly Goldman Sachs chain store sales index, import and export prices, the weekly Johnson Redbook retail sales report and the monthly Treasury budget statement.

FORBES: Comex Gold Higher on Bargain Hunting, Weaker U.S. Dollar Index