PERTH: Australia's Lynas Rare Earths posted a 55 per cent jump in first-quarter revenue on Thursday, helped by record realised prices, while warning that planned shutdowns at its Malaysia and Kalgoorlie facilities would weigh on current-quarter production.

Growing Western demand for non-Chinese critical minerals supply has boosted Lynas' ability to lock in floor-price contracts above market benchmarks, strengthening pricing even as China remains the dominant player in the rare earths sector.

Floor-price agreements now cover more than half of Lynas' production, helping lift its average selling price 88 per cent to a record A$102.1 per kg in the quarter ended Sept 30. The higher prices more than offset a 17.7 per cent decline in rare earth oxide sales volumes.