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April 23 (Reuters) - Newmont Mining Corp, the world's No. 2 gold miner, reported an adjusted quarterly profit that was double the analysts' average estimate, helped by lower costs.
All-in sustaining costs to produce one ounce of gold fell nearly 18 percent to $849 in the first-quarter ended March 31. This cost metric, adopted by producers in 2013, includes sustaining capital, exploration costs and general expenses.
All-in sustaining costs to produce one pound of copper more than halved to $1.73.
"Newmont had a strong start to the year despite lower metal prices," said Chief Executive Officer Gary Goldberg.
"We generated 50 percent higher earnings on 18 percent lower all-in sustaining costs."
Profits were also helped by higher copper production and some delayed spending, said Newmont, which operates mines in the United States, Australia, Peru, Ghana, and Indonesia.
Adjusted net income, which excludes one-time items such as non-cash write downs, rose 89 percent to $229 million, or 46 cents a share, from $121 million, or 24 cents a share, a year earlier.
Analysts on an average expected the miner to report earnings of 23 cents per share, according to Thomson Reuters I/B/E/S.
Sales rose 12 percent to $1.97 billion.
Newmont's shares were trading up 3 percent at $24.11 in extended trading. (Reporting by Susan Taylor in Toronto and Manya Venkatesh in Bengaluru; Editing by Sayantani Ghosh)