Orichalcum ("mountain copper") or aurichalcum ("gold copper") was a metal used in coins during ancient times. Orichalcum was a golden-yellow coloured mixture consisting of both copper and zinc and referred to as brass. The Romans were the first to make coins from orichalcum and were attracted to the metal due to its close resemblance to gold. According to the Greek philosopher Plato (428/427-348-347...