Around 500,000 tonnes of coal will be lost from stocks at South Africa's Richards Bay Coal (RBCT) terminal due to a derailment on Monday night, industry sources said.

Stocks at RBCT, currently 2.9 million tonnes, will drop to 2.4 million as a result. It is not possible to make up the lost tonnage which is seen as a loss to the system after a derailment, the sources said.

Stocks are sufficient for exports to continue smoothly but when levels fall close to 2 million tonnes there are often shortages of certain grades of coal, which can cause loading delays, they said.

A spokesman for Transnet Freight Rail said earlier on Tuesday that the lines would reopen within 40 hours. (Reporting by Jackie Cowhig, editing by Anthony Barker)

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