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Chemical Change in Iron Ore May Have Sunk Giant Vessel

Over the weekend a tragedy unfolded suddenly in the South Atlantic.

Mnet 125371 Stellardaisy

Over the weekend a tragedy unfolded suddenly in the South Atlantic.

The Stellar Daisy, a bulk carrier roughly the size as 100 tennis courts, sunk on route from Brazil. So far, only two of the 24 crew on board have been found and brought to safety.

The South Korean vessel was carrying 266,000 tons of iron ore to China, the world’s biggest importer of the mineral.

While an investigation into the accident is still underway, a theory that the iron ore liquified and shifted the vessel has been floated by an industry blog, Shipwreck Log.

If the theory turns out to be true, it will be one of several maritime accidents blamed on iron or nickel ore liquefaction. In fact, several analysts have raised alarm bells about the issue over the last few years, saying that iron and nickel ore can liquify after periods of prolonged movement and the extra shaking that can occur in rough waves. After the dry cargo liquefies it can then shift in unpredictable ways, which causes the vessel to tilt and capsize more quickly.

This effect was blamed in the 2010 sinking of three ships full of nickel ore in Southeast Asia. The accidents killed 44 crew.  

In 2011, the Australian Journal of Mining published a piece arguing that the potential threat has been too often ignored by the industry.

“Although a cargo may appear to be dry, its core structure may contain sufficient moisture to cause liquefaction,” an expert on the issue said. “It does not take much force to produce or induce liquefaction.”

“People just don’t accept that their cargo is going to liquefy. We need to better understand the properties of nickel ore,” he argued.

Shortly before Stellar Daisy went missing, crew sent a distress message saying that water was entering the ship and that it was breaking apart.

According to the BBC, the search effort for the Stellar Daisy has so far only recovered fuel, debris and empty lifeboats. The ship went down about 2,300 miles off the coast of Uruguay.

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