Higher imports by the world's second-biggest bullion consumer could support benchmark gold prices, which have corrected nearly 17% from an all-time high of $2,072 in August.
Global copper smelting slipped to the lowest levels in at least five years in March as top producer China failed to recover following the Lunar New Year holiday due to supply shortages.
Company said in a statement that it had reached a collective agreement with the mine's worker union, which included a bonus payment of around 4.16 million Chilean pesos ($5,776) but no salary adjustment.