Around 50 workers are expected to lose their jobs at Sibelco’s magnesia mine and processing plant in Queensland.
The company said a workforce restructure would see jobs lost at its mine at Kunwarara as well as its magnesia processing site at Rockhampton, ABC reported.
Sibelco said the cuts would be implemented to improve the profitability of the business.
Peter Lyon from the Australian Manufacturing Workers Union (AMWU) said there would be both voluntary and forced redundancies.
"They'll be cut at the mine site and at Parkhurst production site and it involves permanent employees as well as part-time and casual employees,” Lyon said.
"So people have a week or two to make up their minds about if they want to apply for it or if they just want to hang in and hope they keep their job."
Lyon said the news of job cuts was devastating for local workers.
"I daresay there will be issues from people that will have mortgage stress and marital stress and other problems, especially with Christmas coming up," he said.
"I don't know if central Queensland can deal with it but it's going to be hard, really hard on the area."