International scientists say they've discovered an 18-kilogram meteorite in eastern Antarctica, the largest found in that area in 25 years.

The Brussels-based International Polar Foundation said Thursday the meteorite is an "ordinary chondrite," the most common meteorite. It was discovered Jan. 28, and is undergoing a special thawing process in Japan so water won't penetrate it before it's studied.

During a 40-day expedition, scientists discovered 425 meteorites at an altitude of 2,900 metres, 140 kilometres south of Belgium's Princess Elisabeth Antarctica research base.

While this is the largest found in eastern Antarctica since 1988, a 21.5-kilogram meteorite was found on the continent in 2005, according to the Meteoritical Bulletin Database. The largest in Antarctica was 407 kilograms, found in 1976 or 1977.