The sale by the Greek State of the Cassandra mines in 2003 to the private company, Ellinikos Xrysos, at below market value, amounted to illegal state aid. This was the conclusion reached by the European Commission following a two year investigation based on a complaint. The sale of the mines (which produce gold, copper, silver and zinc) was carried out without an open tender or a market valuation by an independent valuer and was accompanied by a waiver of the customary transaction taxes. The Commission has ordered that the beneficiary must repay €15.3m and interest on the sum to the Greek State.