All gold that shines? Part 1 - How does your gold look like?

Think about this small dialog:

DM: With your last hit you see the live vanish out of the goblin and he sinks to your feet.
Player 1: Cool! I will go through his pockets. Do I find something?
DM: You find 5 gold and 16 silver pieces.

It is more than once that I was frustrated to just say something like that to my players. How about this scene?

DM: With your last hit you see the live vanish out of the goblin and he sinks to your feet.
Player 1: Cool! I will go through his pockets. Do I find something?
DM: You find 5 gold ducats and 16 silver florin.

That sounds much better for my understanding and I would hope that the dialog would continue like this:

Player 1: Wow! Do I know from which kingdom they are?
Player 2 to 1: How old are they? Why do these goblins have these type of coins with them?

Nice role playing opportunities!
But for the sake I fear that this dialog may also be more like this:

Player 1: How much are these in normal gold and silver?
Player 2: Do I have to account for them differently than the other gold?

The first case would open up a lot opportunities for interaction with your world. You can set up things like this:

• Plot hooks. Where does these coins come from? A distant land or perhaps an ancient kingdom
• Interaction: These type of coins may be forbidden to use in the current kingdom because they are minted by an rival kingdom.
• Clues: The coins could lead to a villain from another land that payed the goblins. Think about the Persian gold paid to the Spartan priests in the movie 300.
• Adding depth to your game through emphasizing differences in cultures by their different types of currency. I also thing about different coins for Dwarfs or a magical currency that is made and used by wizards.

But also the second case shows some truth:

• If there are different coin systems: Are there different prices for the daily goods if they are paid in different currencies?
• Adding different coin systems would add also an additional amount of accounting on the player side. If you have a group that love to track their weights, ammunition or material components then they would have no problem with that. But this is likely not the reality.

I'm not sure yet if the pros outweigh the cons.

A more simple solution might be to say that all gold coins are always gold coins. They than may have different names and shapes but all gold coins are always one gold.