Evolution of Yazirian Currency

I've been working on animals native the the yazirian home world and spent significant time on its avian/birds<br /><br />and an idea occured to me about the earlies form of yazirian currency: feathers<br /><br />used for ornamentation a trade/barter system quickly came into play with value based on rarity and difficulting in obtaining<br /><br />latter currencies retain the original words for feather or wing or crest or ruff or even the name of the bird that the feather came from.<br /><br />Of course in the modern Frontier the economies of yazirian worlds are driven by the credit established by PGC<br />but would the yazirians have transitioned to precious metals? or to paper money?<br />