Benchmark three-month copper on the London Metal Exchange (LME) shed 2.6% to $10,136 a tonne.
The metal, widely used in the power and construction industries, was on track for its biggest daily fall since February. Last week, copper hit a record of $10,747.50 a tonne and has jumped 32% so far this year.
Benchmark copper on the London Metal Exchange was up 0.1% at $9,895 a tonne.
Copper prices dipped initially on Friday, but then joined gains in other risky assets such as world stocks, which held near record highs, lifted by strong US data and the Federal Reserve's vow to support the economy.