The bags, which were supposed to contain more than 50 metric tons of nickel, were actually filled with stones, and the warehouse where they were kept was reportedly owned and operated by logistics firm Access World, which is owned by miner and trader Glencore PLC.

If the bags had actually contained nickel, they would have been worth around $1.3 million (£1.06m).

Access World stated that it inspects “warranted bags of nickel briquettes at all locations” but believes the issue to be “an isolated case and specific to one warehouse in Rotterdam”, Fox Business reports.