The giant freighter that mysteriously vanished in the South Pacific may have capsized without warning because of a chemical change in its cargo.

The 266,000 ton South Korean bulk carrier Stellar Daisy disappeared off the coast of Uruguay en route from Brazil to China, hours after issuing a distress signal on Friday.

The ship was carrying 24 people, including 14 Filipinos and eight South Koreans. Two Filipino crew members found floating on life rafts were rescued on Saturday and the search continues for the other 22.

An oil slick detected 2300 miles off the coast indicated that the 1056-foot vessel had probably sunk, according to a statement issued by the Uruguayan Navy.

The Stellar Daisy was reportedly transporting a cargo of iron ore from the Ilha Guaba terminal in Rio de Janeiro to China, where the demand for ore has exploded as the economy grows.

Early reports suggest that the Stellar Daisy, which is classified as a Very Large Ore Carrier, lost stability and quickly sank.

One theory being floated, published in the Shipwreck Log today, is that the ore shifted, causing the vessel to lose balance and capsize.

There have been several documented cases of ships suddenly sinking due to the liquification of iron ore and nickel ore during prolonged movement, such as bumping and shaking that occurs in bad weather.

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