I'm pretty sure the French were on the gold standard in August 1914. Did you mean WWII?
I was talking about 1890’s, when the Long Depression and deflation in France caused a collapse in confidence in the French Government and French business and the value of silver coinage and silver rounds were of equal value by weight.
The US Mint allows private mints like the Franklin Mint to produce silver coinage at a premium to spot (averaging about 10% to 11% over long term) , for years the coinage from these private mints was valued above rounds and below US Mint coinage. In the last month there has been a complete breakdown of the spreads, a US Silver Dollar and a one ounce Silver round of same purity are almost at the same spot price when bought in bulk. Private mints receiving almost no premium on the market compared to blank rounds.
It’s a disturbing break from longstanding trend lines that many silver bugs are proclaiming as the beginning of the end of several fiat currency systems, but they proclaim that pretty often about just about any event that suits their world view.