Here's a question: Gold as money 'evolved' from the barter system, as a better way for people to transact with one another. Silver also found its way into use as a means of transaction/store of value. There is arguably no difference between silver and gold in terms of fundamental properties which make for a sound form of money. Why do we therefore have these two 'precious' metals?
The constraints of physical coinage. The smallest gold coin in the US was roughly the size of a dime and was worth more than a laborers daily wage. Imagine Joe Smith got paid his dime sized gold coin (about 2 grams) and went into a bar for a drink which was 1/10th of a gram. How exactly was he going to spend it? Were people going to mint 1/10th gram coins which were about 1/20th the size of a dime?
You can easily have the tiniest amount of gold in a plastic wrapper. Hence one could wrap infinitesimal amounts of gold safely and trade it without the need of a minted coin.
Circa 1700? Gold is no longer used as a circulating currency. When it was used as "money", the technology needed to mint, authenticate, and transport sub gram gold coins simply didn't exist.
Sorry for the side-track, I was obviously too tired and didn't read your post properly
I was just thinking of the people in the US (can't find a link) with tiny amounts of gold and a laminating machine campaigning for using gold as a currency, but they are clearly irrelevant in how there came to be a use for silver in coinage back in the day.
