South Korea's Ki Bo Bae took women's individual archery gold in a
against Mexico's Aida Roman.
Former world number one Ki needed nine with her last arrow in the fifth set but could only manage an eight, taking the final into sudden death.
Both archers struck eight but Bae was closer to the centre of the target and ensured South Korea's second archery gold.
Mexico's Mariana Avitia beat America's Khatuna Lorig to take bronze.
Britain's two competitors,
were beaten at the last-16 stage - Folkard to Avitia.
Ki, who had already helped South Korea
win team archery gold
at London 2012, went into an early lead in the final before Roman fought back to level the match after the third set.
It looked like Ki was on for the gold when she struck three consecutive maximums in the fourth, but she could not finish the job in the final set.
Lorig, who lost the bronze medal shoot-out, was competing in her fifth successive Olympics for a third different country.
The 38-year-old, who trained actress Jennifer Lawrence on how to fire a bow for her role in 'Hunger Games', represented the Soviet Union in 1992, winning bronze, and Georgia in 1996 and 2000.
She also won a bronze for the United States in Beijing in 2008.