Well hmm, maybe thats part of the issue...

The magic of the world can only be accessed through the gem stones, one who is capable puts the magic into the gem for use, otherwise its untappable. Anyone and their dog can use Level 1, or the small coins to do simple things, like parlor tricks, or alternating somethings color etc, mostly a nuisance in most cases. Level 2 or the medium coins are for those that are gifted, or the trained wizards who are able to do more powerful things, then Level 3 or the Large coins, are only used by the trained Gifted who can perform amazing things with the power. So if the Hoard is filled with small coins, well it might be a small fortune and a person can become a none magical noble for it, but if they were to have medium or large coins (and were able to tap into them) they could be the next "dark lord" with infinite or seemingly infinite power.

So based on the (standard) they understand that the larger coins are worth more ( like a gold flake compared to a gold nugget, just know its worth more even though its the same thing) the Majority of the people don't know the use for the larger coins, or even most of the smaller ones, only the trained and those fluke people know they can use magic with the gem alone (if infused).

Does that answer or help what your asking??