While the price of gold is going through the roof on world bullion markets, Ethiopia's central bank is anxiously checking the contents of its vaults to see just how much "fool's gold" is in there.

The first hint that something was wrong reportedly came when the Ethiopian central bank exported a consignment of gold bars to South Africa.

The South Africans sent the shipment back complaining they had been sold gilded steel.

Investigations revealed that the bank had bought a whole consignment of fake gold from a supplier, who is now under arrest.

Other arrests followed, including business associates of the man accused, national bank officials, and chemists from the national geological survey whose job it is to assay the bank's purchases of gold and certify that they are real.