Copper notched its biggest one-day advance since May 2013 as investors calculated that a trade dispute between the United States and China could damage economic growth less than feared.
Benchmark copper on the London Metal Exchange closed on Friday at $6,363 a tonne, up 4.6 percent, after touching its highest since July. It was up 6.5 percent on the week.
Worries that trade barriers would curb demand for commodities had pushed industrial metals sharply lower, with copper plunging from a high of $7,348 in June to a 14-month low of $5,773 last month.
But these concerns eased after tariffs announced this week were set at lower rates than had been expected and China, the world's largest metals consumer, announced steps to boost its economy.
"There's been quite a change in sentiment," said Saxo Bank analyst Ole Hansen.
But copper would have to move above Fibonacci technical resistance at $6,375 a tonne to cement its rally, he added.