Bimetallism in France
Bimetallism reflects a period in history when commerce was conducted in multiple metals, but chiefly gold and silver, and the problems that resulted when the state attempted to fix the exchange rate between coins contrary to the manner in which the metals were valued in the market.
There have been instances, particularly in France, when bimetallism was seen as a remedy to the fluctuations in the value of metal based on the notion of diversification: it was presumed that the fluctuation of a single metal would be more dramatic and unpredictable than the fluctuation of a portfolio of two different ones.
(EN: And again, it becomes a very detailed and idiosyncratic history lesson about a topic that is no longer relevant to modern economies, so I'm skipping the incidental details.)