LONDON (Reuters) – Copper prices were on Friday set for their biggest weekly fall in a year, down around 6.5%, as investors worried that efforts by central banks to stem inflation will stifle global economic growth and reduce demand for metals. Other industrial metals also tumbled, with nickel shedding around 13% this week and tin sliding 22%, its biggest weekly slump since at least 2005. “There is a risk of further losses,” said independent analyst Robin Bhar. “A sharp economic slowdown or recession seems to be on the cards.” Benchmark copper on the London Metal Exchange was 0.5% lower at $8,…