Tolkienists.org

… Coins are mentioned a few times in The Lord of the Rings, including the price of Bill, the pony — ​“twelve silver pennies” (LRC §1.11.032) — but I’m not aware that these coins are ever described in any detail — and whose coins are they and where do they come from?

Because all such information is lacking, I imagine that the Nazgul, if telling the truth, has, somewhere, a sack of coins from Mordor itself — gold coins, at that. Western Mordor, at least the part we see in Sam and Frodo’s travels, seems utterly barren, but Sauron has armies to feed and the myriad horses and mules and oxen needed to carry such armies beyond his gates, and that food and those beasts have to come from somewhere. Even if we presume that much can be produced from green lands beyond the Sea of Nurnen, Sauron has allies farther south in Harad, suggesting that he has commerce of some sort with them and, as we know from those twelve silver pennies, Middle-earth appears not to be based upon a barter-system.

So what would such coins look like? …