A molybdenum plant will begin operating next month.

The $130 million project will create about 15 full time jobs at the mine.

Molybdenum is a silvery-white metal used in steels and superalloys to enhance strength, prevent corrosion and reduce brittleness, as well as having uses in lubricants, fertilisers and pigments.

The plant's future was confirmed in Newcrest's just-released annual report.

"Newcrest expects to achieve first production from the Molybdenum Plant by the end of September 2021," it said.

"The Molybdenum Plant is expected to deliver an additional revenue stream for Cadia in the form of molybdenum concentrate."

A statement from Cadia said molybdenum was a by-product of copper mining.

"Construction of Australia's first moly processing plant started in February 2020, after board approval in June 2019," it said.

"The plant will generate an additional revenue stream of about $45 million per annum.

"Moly is extracted from the copper concentrate stream prior to it being pumped to Blayney, producing a moly concentrate at Cadia that will be approximately 50 per cent molybdenum and be in a dry powder form."

The annual report also confirmed Cadia's expansion program with a new cave had moved to the next stage.

Newcrest managing director and CEO, Sandeep Biswas, said the board had approved the Cadia PC1-2 project to a feasibility study stage and had approved an 'early works program' to establish infrastructure.

"PC1-2 has an attractive rate of return and is expected to help sustain Cadia's position as a tier 1, low-cost producer for decades to come," he said.

Mr Biswas said $120 million for the early works program had been approved with a start likely in the December 2021 quarter.

"The development of the PC1-2 cave is the next step in Cadia's block caving journey," he said.

"The study underpins an optimised mine design which we expect will deliver higher gold and copper grades and enable the deferral of capital expenditure in the medium term."

The report said the company had been free of fatalities for six years and production had not been affected by COVID outbreaks.