(Adds analyst comment, updates shares)
By Karen Rebelo
April 29 (Reuters) - Aquarius Platinum Ltd, the world's fourth-largest platinum miner, reported a fall in quarterly revenue and core operational earnings as a prolonged strike in South Africa's platinum belt failed to push up platinum prices.
Aquarius is unaffected by the strike, giving it an opportunity to benefit from a shortage in supply.
The company's London-listed shares rose as much as 6.3 percent but analysts said that was because a record date for a $225 million rights issue had passed, rather than the earnings.
The miner reported mine earnings before interest, tax, depreciation and amortization (EBITDA) of $11 million for the quarter ended March 31, down from $30 million a year earlier.
Revenue fell to $60 million from $100 million a year ago. However, revenue and mine EBITDA rose from the previous quarter, driven by higher output at its main Kroondal mine.
Platinum prices have not jumped despite more than half of primary platinum production being interupted for more than three months by the strike affecting other miners.
Platinum prices have only risen about 3 percent since the start of the year.
The miner said average platinum group metals (PGM) basket price in dollar terms was down 11 percent from a year earlier and increased 2 percent from the previous quarter.
"I think pricing was expected to benefit producers like Aquarius that aren't affected by the strikes, that hasn't taken place," Panmure Gordon analyst Troy O'Dwyer said.
London-listed Aquarius Platinum (Frankfurt: QPMC.F - news) was largely shielded from the strike as it signed a one-year agreement with the National Union of Mineworkers last June, a rare deal in an industry rocked by labour unrest and a bloody union turf war. (http://r.reuters.com/bem88v)
The world's top three platinum miners - Anglo American (LSE: AAL.L - news) Platinum (Amplats), Impala Platinum Holdings Ltd and Lonmin Plc (LSE: LMI.L - news) - are caught in the 14-week strike over a wage dispute that has so far cost producers more than 15 billion rand ($1.4 billion).
Acquarius said attributable production from operating mines remained ahead of its guidance and was in line compared to production in the third-quarter of last year.
The Kroondal mine, a venture with Anglo American Platinum about 120 km northwest of Johannesburg, accounts for about 60 percent of Acquarius' produciton.
Acquarius shares touched a high of 21 pence before easing back a little to 20.98 by 0951 GMT.
The company plans to use much of the proceeds of its rights issue to repay convertible bonds.
(Editing by Gopakumar Warrier and Rodney Joyce)