The London Metal Exchange was forced to delay a resumption of trading in nickel during Asian hours until March 27th, after it discovered “irregularities” at one of its warehouses with bagged nickel briquettes.

In a statement, the LME noted it had to cancel nine nickel warrants at one of its facilities after finding bagged nickel briquettes stored there were not of the weight their contract specified.

In its statement, the LME said, “The exchange has received information that a number of physical nickel shipments out of one specific facility of an LME-licensed warehouse operator have been subject to such irregularities.”

A warrant is roughly equal to about six tons of nickel, which would mean the irregularities affected about 54 tons of the exchange’s nickel. According to the exchange, this represented about 0.14% of its live nickel inventories. Although the exchange said there was no reason to suspect any other warehouses were affected, it has asked all its operators to recheck its stored warranted nickel. It also noted that metals which do not allow bagged delivery, “are not susceptible to this type of irregularity.”

The exchange did not specify what warehouse was affected or its location, however several reports, citing sources, said the affected bags were actually filled with stones. Other reports indicated the fake nickel was being stored at a warehouse in Rotterdam, operated by Access World.

The report follows another scandal involving nickel at Trafigura. The trading giant reported last month that it had found fraud in shipments which did not contain the metal the contract specified, and that this would force the company to endure millions in losses. Trafigura has since begun legal proceedings over the fraud against Prateek Gupta, an Indian metals trader, as well as his companies.