London Mining, one of the few junior iron ore companies currently producing in West Africa, maintained its 2013 sales forecast of 3.6 million to 3.8 million dry metric tonnes.

"The second plant ramp up was completed six weeks ahead of schedule and solid production performance from both plants allows us to move to the higher end of production guidance for the year," Chief Executive Graeme Hossie said in a statement.

Production in the second quarter ended June 30 rose to 963,000 wet metric tonnes of iron ore concentrate, up 36 percent from the preceding quarter, while sales rose 72 percent to 1,014,000 wet metric tonnes.

The company, which also has operations in Greenland, Saudi Arabia and Colombia, reported a smaller full-year loss in March and had then said it expected output from the mine to more than double in 2013.

"This is a good set of results, in our view; given the stage of the ramp up at Marampa delivery remains crucial to driving a rerating of the stock," Citi analyst Michael Flitton said in a note.

London Mining said that its plan to further expand capacity at Marampa to 5 million tonnes per year by the end of 2013 was on track.

"We remain buyers on value grounds, although we do expect iron ore prices to soften from their current levels ($130/t) in the second half," Liberum Capital analyst Richard Knights said in a note.

Benchmark 62-percent grade iron ore <.IO62-CNI=SI> climbed 1.1 percent to $130.4 a tonne on Wednesday, its highest level since April 30, as firmer steel prices in China encouraged purchases of the raw material amid limited availability of spot cargoes.

Shares in the company were up 6 percent at 92 pence at 0839 GMT on Thursday on the London Stock Exchange.

(Reporting by Karen Rebelo and Abhirup Roy in Bangalore; Editing by Supriya Kurane)