NEW YORK—Gold prices traded higher for a second day Tuesday after the dollar lost ground against the euro, boosting demand for precious metals as inflation hedge. Silver and copper also rose.

Other commodities traded mixed, with crude oil rebounding back above $114 a barrel and wheat and soybeans falling.

The dollar turned lower against some rival currencies after the U.S. government said wholesale inflation shot higher in July. The 15-nation euro rose to $1.4768 in late New York trading from $1.4697 late Monday.

A falling dollar generally encourages investo...