West Marshes - Coinage

From left, clockwise: A noble, crown, rupee, and cent. The cubes are standard d6s, for reference.

I'm throwing out the 4e coins basically entirely, because according to the DMG the players should have found something like six million pounds of gold (as a party), in addition to magic items, by the time they reach Paragon tier. This is the point at which they're supposed to be "starting" to become famous and interacting with things on a national level, such as commanding or ruling nations.

That outrageous number is for two reasons, one of which is that coins in D&D are described as extremely heavy compared to historical coins. The other reason is because the amounts given for treasure and the cost of magic items are mostly arbitrary, and tend to favor handing out huge piles of gold or platinum as a rule. The prices of everything else are scaled to match.

So in my world, as minted by the Empire of the Unnamed Kings, to which Blanche-Piste belongs, there are four coins.

The base unit is the "noble". This is the second largest coin, 30mm in diameter (about the size of a US half dollar) and 0.03lbs of near pure silver. One of these coins is the equivalent, usage-wise, of a modern $20 bill: larger than any single transaction you're likely to make, but accepted pretty much anywhere and easy to make change for.

The second coin is the "cent". This is a third largest coin, 20mm in diameter (about the size of a US nickel), worth 1/100th of a noble, and is 0.01lbs of near pure copper. This coin is used to make change or for small transactions among commoners, it is something like a US $0.50 or $0.25 coin in the mind of the average person.

The third coin is the "rupee". This is the smallest coin, and is worth 1/10th of a noble, or 10 cents. It is 19mm in diameter, smaller than a cent (about the size of a US penny), and is not pure silver, but rather an alloy of silver and copper, weighing in at 0.006lbs. This is the coin most commonly used among commoners, it would be equivalent, to something like a US $1 bill.

The last coin is the "crown". This coin is 38mm in diameter (about the size of a US silver dollar), the largest coin, and 0.04lbs of near pure gold. It is worth 100 nobles, and thus most commoners will rarely handle more than a handful of these per year, if any. It is difficult to make change for, and used mostly among merchants for large transactions.

Larger transactions, such as gifts between kingdoms or purchases of entire regions, are made using silver or gold bars.

1 pound of cents/copper: 1 noble, 100 coins.
1 pound of rupees: Roughly 16 nobles, 166 coins.
1 pound of nobles/silver: Roughly 33 nobles, 33 coins.
1 pound of crowns/gold: 2,500 nobles, 25 coins.

To put it into real world terms:

If one were to go out to lunch in an average tavern, you would go in with 1 noble (a silver coin), buy a meal, a drink or two, and expect to get back a rupee or two as change.

Crowns, on the other hand, are very rare; try to imagine something like a $1000 USD bill: the amount is something you might expect to pay for certain things, but rarely will you need to actually handle crowns for transactions. You're more likely to just use 100 nobles.

All prices are measured in nobles. When a person sees a crown, they don't think of it as "one crown," but rather, "a hundred noble coin." A rupee is thought of as, "10 cents." The decimal system is in use, so one might see prices such as "23.50", which would be 23 nobles and 50 cents. If you gave the merchant 24 nobles, you would get 5 rupees as change.

The average town-person will carry maybe 1-10 each of nobles, rupees, and cents on their person.