The milestone comes two years after commercial production started on October 1, 2016, when the mine was built on time and around 20% under budget for US$525 million.

This year, the company completed the second phase of the mine, including the construction of a primary crusher to process harder ore as the mine gets deeper, on time and within budget.

The Merian mine has a mine life of about 15 years.

Newmont's shares dropped 0.56% Wednesday to $32.11 per share.