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SANTIAGO, Jan 13 (Reuters) - Chile's copper production is expected to reach between 5.5 million and 5.7 million metric tons in 2026, up from an estimated 5.4 million tons last year, the national mining association Sonami said on Tuesday.

Sonami, which represents mining companies, described the outlook as upbeat despite ongoing operational challenges.

"We could call it a rather optimistic scenario," Sonami President Jorge Riesco said. "We have positive financial and commercial figures, but significant structural challenges in operations and investment at most mining sites."

The group forecast copper prices to average $4.50 per pound this year. Sector investments were estimated at $26.8 billion for the 2025–2029 period.

(Reporting by Fabian Cambero; editing by Gabriel Araujo)

((natalia.siniawski@thomsonreuters.com;))