Americans Kerri Walsh and Misty May beat Brazilians Adriana Behar and Shelda Bede to win the women's beach volleyball title 21-17 21-11.
After the victory, May sprinkled the ashes of her mother - who died of cancer two years ago - over the court.
"Everybody else's family is here, why couldn't I bring my family?" said May.
Americans Holly McPeak and Elaine Youngs took bronze after beating Natalie Cook and Nicole Sanderson of Australia 21-18 15-21 15-9.
The Australian pair's challenge was hampered when Cook, gold medallist in 2000, aggravated a shoulder injury.