Newcrest Mining expects to save up to $US2.5 billion by splitting the development plan for a mine in Papua New Guinea into two stages.
The first stage of the Golpu gold and copper project will target the higher value portion of the ore body, and is forecast to cost $US2.3 billion.
A pre-feasibility study for stage two will be updated, and the estimated capital expenditure over the life of the mine is expected to be $US3.1 billion.
The joint venture project with Harmony Gold Mining was originally estimated to cost $US4.8 billion.
"By targeting the high value core of the ore body first, we have increased the economic returns from the mine by being cash flow positive earlier in the life of the mine," chief executive Sandeep Biswas said.
"Progressing stage one to the feasibility study stage aligns with Newcrest's strategy of profitable growth through low cost operations."
Both the stage one feasibility study and stage two pre-feasibility study are expected to be updated by the end of calendar 2015.
Production at stage one is forecast to begin in 2020, with annual output expected to peak at 320,000 ounces of gold and 150,000 tonnes of copper in 2025.
Production for the original project was forecast to peak at 550,000 ounces of gold and 330,000 ounces of copper.
The Golpu deposit forms part of the Wafi-Golpu project, 65 kilometres from Lae in PNG.
The PNG government has an option to take a 30 per cent stake in the project, which would reduce Newcrest and Harmony's equal 50 per cent shares to 35 per cent respectively.