Shares in Alumina Ltd rose nearly five% after US partner posted a sharp loss in the second quarter on restructuring costs.
At 1035 AEST Alumina was 4.75% higher at $1.0475, against a benchmark index rise of 0.89%.
Despite the loss, Aluminium producer Alcoa remains bullish on the global outlook for aluminium.
For the three months to June 30, Alcoa posted a loss of $US119 million, a huge drop on the $US2 million loss it posted in the previous corresponding period.
The result translates to a loss of 11 cents per share.
Alcoa's loss included a $US42 million charge on the closing of the two Soderberg potlines at its Baie-Comeau smelter in Québec, and a $US34 million charge taken on the looming closure of its Fusina smelter in Italy.
"Alcoa continues to project 7% global aluminum demand growth in 2013 and essentially balanced alumina and aluminum markets," the group said.
However, the group's core earnings increased.
"In our value-add businesses we reached another milestone with record profitability in our downstream business while acting decisively to defy the headwinds of falling metal prices in our upstream businesses," chairman and chief executive Klaus Kleinfeld said.
Tough quarter for aluminium: Alumina
Commenting on the Alcoa results, Alumina Ltd chief executive officer John Bevan said it had been "a tough quarter for aluminium prices" but spot alumina prices remain relatively stable.
"Improvements in productivity and costs have seen margins remain reasonably steady for alumina," he said.
"The recent decline in the Australian dollar and Brazilian Real is a positive development and, if sustained, will deliver financial benefits through lower production costs."
Alcoa World and Aluminium Chemicals (AWAC) produced four million tonnes of alumina in the second quarter, the group said.
Alumina disclosed it received distributions of US$4 million from AWAC during the quarter, and that on on July 1 it received a fully-franked dividend of US$25 million.
"The total of dividends and distributions received by Alumina Limited during 2013 is US$54 million," the group said.