Currency in Spades:
-Precious Metal based, for the most part. The super fancy coins are made of gemstones these days as there is a mild boom of newly-taught Geomagers with Crystallomagy skills, and as such they all just hold the amount of 'a lot.'
-Coin value from lowest to highest is as follows: Coppers, Bronzes, Steels, Silvers, Golds, White/Black-Golds, Gems.
-Copper coins are kinda expected to be destroyed/used up over time for various things, so they don't have much detail. Just a simple Spade crest, the year it was printed in, and where it was printed. Other side is blank as a lot of in-training Ferromagers or Chain Scribes use them to practice detail maneuvering/etching on them.
-Bronzes have the same front as coppers, but the back has an image of Magmoran Mountain from the outside. Smoke's rising from it's tip.
-Steels are the most commonly used coin. As such, they're made of a durable metal, have a slightly more detailed Spade crest on the front, and the back is an image of Leigh, the main city where a majority of people live and work. You can tell how old a Steel coin is by how large Leigh looks on the back, as the design is updated every few years.
-Silvers are like, ~20$ coins. Good for a lot of luxuries in Spades, but not the super high-tier luxuries. Same Spade crest as Steels, image on the back is of the Thundering Docks
-Golds are your high-end coins. Used for biiiig purchases and making it rain. (Painfully.) The front has an even more detailed Spade crest, and the back is an image of the Vorpal Mines' main shaft into the dark below, or of Eletio proper. The back design swaps every minted batch.
-Black/White Golds are status symbol coins, and also used to mark historic occasions while also being currency. They have a grand Spade crest on them. They're an alloy of Gold and cobalt/silver. They're used to mark events regarding Royalty, such as the crowning of a new king, the passing of an old, or any great achievements done during a king's lifetime. What determines if a newly-minted B/W Gold is B or W depends on which royal family the coin is being minted for. Since Tridekas belongs to the Regulus family, all B/W Gold coins printed during his reign have been White Golds. He's only had a few issued, notably for his coronation, the rediscovery of the Crystal Codices (Why gem coins can even be made in the first place, some old Geomager got too paranoid and locked all that knowledge away), the establishing of the Chainway between Eletio and Leigh, and the fact that Moves have started to occur again.
If anyone knew where the Regulas family was or what they were up to, they'd probably have a few 'Lesser Black Golds' made for their own achievements. Same material as a usual B/W Gold, just smaller in size.
-Gem coins are the newest, most statusy-symbol and wildly impractical to ever use coins. The front is the same as a Gold coin, but the backs are kinda... whatever and wherever. Sky's the limit, as long as it's not too offensive, really. Mikiri made one with Tridekas tripping over a table and auctioned it off for charity. It sold for a fuckload and Tri was trying not to wheeze himself unconscious from laughter the entire time.