The operations, which include 10 underground and 12 open pit mines in the southwestern U.S. state and rank as the largest global gold producing complex, had produced a total of 4.1 million ounces of gold in 2018.

Barrick and Newmont agreed to form the joint venture in Nevada in March after Barrick withdrew its $18 billion offer for its rival, ending a hostile takeover bid that sought to unite the world's two largest gold producers.

Barrick and Newmont Goldcorp have 61.5% and 38.5% stakes, respectively, in the joint venture, which was officially launched on Monday.

Barrick, which also operates the joint venture, Nevada Gold Mines LLC, estimates cost of sales there in the range of $940 to $970 per ounce, while all in sustaining costs are expected to be $920 to $950 per ounce for the second half of the year.

By combining their operations, Barrick and Newmont had hoped to save more than $5 billion over the next 20 years, at a time when gold miners have struggled with a loss of investor confidence and constraints on funding projects.

Barrick said on Monday that it expected to deliver cost savings of up to $500 million per year over the first five years from 2020, which will fall thereafter.

(Reporting by Arathy S Nair in Bengaluru; Editing by James Emmanuel)