Re: What exactly is orchalcum?

"Orchalcum" is a misspelling of "orichalcum", the Latin form of orichalc (there are a handful of webpages that use this same misspelling, suggesting a common misspelled source). The OED gives the etymology of "orichalc" as coming from the Greek "mountain copper". The word was originally applied to a specific yellow copper ore or brass. In one of the Homeric Hymns, there is a reference to Aphrodite wearing earrings made of "orichalc and costly gold", suggesting that the early Greeks prized the metal but placed less value on it than gold. Probably because of the sparse mention of orichalc in Greek literature, by the Middle Ages the term came to represent a precious metal of unknown composition. The most interesting thing about orichalc is how the word and the metal have diverged in their value - orichalc came to represent a fabulous metal of tremendous worth, while brass became a cheap, working alloy - all because the Greeks' yellow ore that produced "native" brass was rare and therefore considered valuable in an age before brass alloying was well understood.