NEW YORK—Gold prices rebounded Monday, pushing back above $800 an ounce as investors went bargain buying after the metal’s massive sell-off last week. Silver also rose.

In other commodities, crude oil fell below $113 a barrel as Tropical Storm Fay headed for Florida but stayed away from major oil installations in the Gulf of Mexico.

After plunging below $800 on Friday for the first time since late last year, gold had a modest recovery as new buyers sought steep discounts from the metal’s all-time highs above $1,000 an ounce reached earlier this year.

Gold fo...