I kind of figured that might be how it works, but honestly trading one coin for another one doesn't make much sense either since you didn't liquidate the asset into capital/currency.
At the time of the exchange it's like trading x amount of gold for x amount of silver.
They are both in flux at any given moment, but at the time of the trade it seems like it's the pocket example except your 1 gold coin is 10 silver coins.