To be honest, a simple encyclopedia-style paragraph introducing the money would suffice; the traditional conworlding approach is, after all, to emulate Wikipedia as much as possible. But if you feel like putting together a bespoke piece, both a longer-form description of your design choices (probably again from an in-world perspective) or an article discussing your methods would both be valuable contributions to the community. Personally I'm more inclined to the former—you've described your methods before in a forum post, but worldbuilding is an endless font of material...