Australia's Lynas Corp. Ltd. delayed plans to develop another rare-earths deposit in Western Australia amid weakening prices for the minerals, used to produce everything from hybrid cars to wind turbines.

The Sydney-based company, which last year completed a scoping study on the Duncan deposit at its Mount Weld site, said Wednesday it would postpone further development work as it looks to reduce operating costs.

Lynas said its newly expanded Malaysian rare-earths processing facilities would be ready to begin production by the end of September, but reiterated that there was no immediate plan to increase output unless market conditions improved.

Lynas built the Malaysian plant with the ambition of breaking China's grip on the rare-earths market and profiting from rising demand for elements used in products like iPads. But its plans have been undermined by weakening prices.

Chinese companies currently account for more than 90% of global supply. At full capacity, Lynas's Malaysian facilities could produce up to a fifth of annual global output--making the company potentially among the world's biggest rare-earths suppliers.

Though rare-earth prices have improved modestly over the past few weeks, they remain significantly lower than a year ago. Lynas said prices for the rare earths it produces fell by about a fifth in the three months through June. The company produced 144 tons of rare earths and shipped 117 tons to customers in the same three-month period after starting production in Malaysia in February.