I mentioned in the first post on currency that I would consider using ratios of 28:1 (iron to copper), 13:1 (copper to silver), and 4:1 (silver to gold) in my currency system. For me, the main reason to use these ratios is to keep the theme of using the important numbers derived from the Cyclic Calendar 28 (days in a month), 13 (months in a year), 4 (years in a cycle), and 25 (cycles in a century).
The currency system already uses these numbers as denominations: 28 iron munts in a copper din; 13 copper dins in a silver talon; 4 silver talons in a gold zlot; and 25 gold zlots in a gold baal. I have also used those numbers in the weights and measures system I created for my fantasy world (part 1 and part 2).
Originally I decided against using the numbers as the ratio values for metals because an iron munt would have to be 10 grams, instead of 6 (explained shortly), and gold would only be four times more valuable than silver, which is quite far off historically and in a typical fantasy context. Furthermore, historically speaking, silver isn’t close be being worth 13 times the value of copper. Bet hey, it’s fantasy, I can do what I want. Though, I want the world to be believable and relatable.
If i were to create a world where copper was more valuable than gold, I’d need to have a reason for why copper was so precious–copper being more valuable would be against our traditional way of thinking. For this reason, I also thought I’d need to think of a reason silver is so valuable in my world–if gold was only 4 times more valuable–but I don’t. Gold is still more valuable and that sits right in our minds. I also have a perfectly good reason. 28, 13, 4 and 25 are important numbers; they are prevalent in my systems. It is perfectly acceptable that precious metals, which are used as currency, also follow this system.
Before I show the main calculations, I’ll clarify why an iron munt would have to weigh 10 grams instead of 6. If an iron munt weighed 6 grams and the ratios were 28:1, 13:1 and 4:1, both a gold zlot and copper half-din would be tiny coins–too small–0.31cm3 and 0.33cm3 respectively. When I first created the currency system, based on research, I decided I didn’t want my coins to be less than 0.5cm3.
First let’s look at the value difference created by the new ratios when measures against gold–the most valuable metal.
With the new ratios iron loses a lot of value against gold–it would require 60% more grams of iron to equal one gram of gold. However, the value of both copper and silver to gold have dropped; silver quite dramatically. You’d need 20% less copper for the equivalent weight in gold, but 60% less silver for the equivalent weight in gold.
Next we can look at the weight of coins compared to their weight under the original system. All coins in the new system will weigh the same (except the baal), 10g, because the ratios and denominations are the same (28, 13, 4, and 25).
The table doesn’t show the original weight of an iron munt, which was 6 grams. While the iron munt has increased by 4g, a copper din decreased 2g (12g to 10g), a silver talon decreased by a massive 14g (24g to 10g), and a gold zlot increased negligibly from 9.6g to 10g. The baal, which is 25 zlots and gold to gold, increased from 240g to 250g.
Finally, we can see how the new coin weights affect the size (cubic centimetres) of the coins.
The biggest differences are the silver talon, which is less than half its original size, and iron munt, which is over 50% larger than it’s original size.
Coin sizes and weights are perfectly reasonable in both systems, though arguably better in the new system due to the decrease in weight of the silver talon. Given this, either system is perfectly reasonable and acceptable. Both hold some advantage over the other.
The main advantage of the original system is maintaining the high value of gold above both silver and copper. Whereas, the main advantage of the new system is lore–the key numbers are not just denominations, but also used to determine the ratio value of the metals. This is also explanation enough without having to work some reason into the world explaining why gold is only 4 times more valuable than silver, and why silver is 12 times more valuable than copper, when neither is true throughout history. It’s fantasy, it’s not about realism, but, in my opinion, making things relatable and believable is important. To this effect gold is still more valuable than silver, which in turn is more valuable than copper.
Furthermore, the price of metals traditionally is not only determine by customer demand, but the cost to produce. If the only iron deposits were hundreds of miles away and scarce, but gold was somewhat plentiful locally, it’s perfectly conceivable that iron would be the more valuable.