Foreign coins were circulated much more than United States coins were up through most of the 19th Century. US coins were much rarer than the common coin and they didn't circulate often. It wasn't until the mid/late 1800's when coinage acts were passed to prevent 3rd party mints from making legal tender coins. At this time there was an extreme shortage of coins and the majority of trade was done through barter. In the 1800s there was a variety of non us coins in circulation. It wasn't until the early 20th century when there was enough coins made to satisfy the needs of Americans. The other coins slowly fell out of circulation. Interestingly enough, most of the odd denomination coins were created to make change with popular foreign coins like centavos. Like said above, each reale was equal to a bit. 8 reales equals one dollar. American coins and spanish/mexican coins were freely traded. It's very interesting that you can't pay for more than $5 worth of goods with silver coins and you can't use more than $0.25 worth of nickels and pennies to pay for a purchase. I guess paying for food at McDonalds with a handful of change is illegal.
Well not quite. That law dealt with legal tender issue only as nickels & cents were not legal tender prior to the law being passed. And since we don't even use silver coins anymore - the rest of it hardly applies. Then of course you have to take into account all of the laws that have been passed since then that supercede the law of 1873. But I get your point.