Updates with background in paragraph 2, adds further details in paragraph 5

Feb 26 (Reuters) - Australia's Lynas Rare Earths LYC.AX reported its best first-half profit in three years on Thursday, helped by higher sales volumes and elevated commodity prices.

Beijing's easing of export controls has helped unwind an earlier supply glut in China, pushing up the domestic benchmark price that underpins sales for much of Lynas' output.

The world's largest rare-earths producer outside China logged a net profit after tax of A$80.2 million ($57.13 million) for the six months ended December 31, far surpassing the A$5.9 million profit reported a year ago.

The net profit, however, missed the Visible Alpha consensus estimate of A$91.8 million.

A spate of power failures at Lynas' Kalgoorlie plant in Western Australia in November resulted in a notable production slump and higher cost of sales.

The company did not declare an interim dividend.

($1 = 1.4037 Australian dollars)

(Reporting by Shivangi Lahiri and Aamir Shaik Khalid in Bengaluru; Editing by Shinjini Ganguli)

((Aamir.SheikKhalid@thomsonreuters.com;))