According to Bloomberg, this could strengthen the case for the Federal Reserve to up interest rates, with Labour Department data showing payroll gains accelerated last month when compared with August's figures.
Bullion for immediate delivery lost 0.2% to settle at $US1112.63 an ounce.
Weakened manufacturing in the US has dented copper prices, as the sector stagnated in the face of a strong dollar and faulty overseas markets.
The metal ended its worst quarter since the first three months of 2014.
Prices are down 18% this year as China - the world's largest consumer - heads for its slowest growth since 1990.
December delivery for copper futures fell 1.6% to $US2.3045 per pound at the Commodities Exchange in New York, while copper for delivery in three months decreased 1.3% to $5095 per tonne in London.