Copper

orichalcum was a real metal, although its legendary status makes it a bit of a mix between history and myth. While it is heavily featured as a magical, incredibly powerful substance in fantasy games and comic books, historians and scientists agree it was actually a highly valued, ancient copper-zinc alloy—essentially a form of early brass. 

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The origins and realities of the metal are split between ancient texts and archaeological discoveries: 

• Plato's Atlantis: In 360 BC, the Greek philosopher Plato wrote about orichalcum in his dialogues Critias and Timaeus. He described it as a rare, glowing metal mined in Atlantis that was second only to gold in value, used to cover the outer walls and temples of the legendary lost city.

• The 2015 Discovery: For centuries, historians debated whether orichalcum was a purely mythical substance or a lost material. However, in 2015, marine archaeologists discovered 47 orichalcum ingots in a 2,600-year-old shipwreck off the coast of Sicily. Scientific analysis revealed the ingots were composed of roughly  copper,  to  zinc, and small amounts of lead and iron—proving it was a real, tangible copper-zinc alloy.

• Roman Coinage: Beyond the myth of Atlantis, orichalcum was historically utilized by the Roman Empire. The Romans used the alloy (often referred to as aurichalcum) to mint some of their largest currency, such as the sestertius and dupondius coins. When freshly minted, orichalcum has a bright, shining, gold-like appearance, which is exactly why the Romans favored it