You may remember a previous blog post where we discussed electrum – a naturally occurring alloy made of gold and silver. Electrum was used through ancient times as coinage and was very important. There is another metal that predates it, but historians wonder whether it really existed or if it was just another alloy.
In several ancient writings (especially in Plato’s Critias) a precious metal called orichalcum – second only to gold in value – is mentioned several times. The name derives from Greek and means “mountain copper” or “mountain metal.” Allegedly, the lost city of Atlantis was built mostly of orichalcum – which gave the city a ruddy or bronze-ish appearance.
But what exactly is orichalcum? Ancient texts never specifically say whether it is an alloy or a pure metal. Some texts mention mines running out of orichalcum which may explain why – if it was a pure metal – it is no longer around.
The sestertius and dupondius coins issued by the Roman Empire were supposed to be made of orichalcum, but are actually a bronze-copper alloy. Most historians agree that orichalcum was actually a copper alloy, possibly mixed with gold, tin, or zinc and brass.