I know languages can be very old, so I realize this might not be restricted to the modern-day country France.
As a side-note, this is true of other languages too in the Latin-based Romance family. E.g. "arginți" (literally: pieces of silver) is an old Romanian word that meant "money" or "coins". And the Latin word "argentum", which predates and is cognate with all of these terms, comes from a proto-indo-european root that means "white".
So, yes, your intuition regarding languages is correct.
Coincidentally, in Mexican Spanish, silver (plata) can be used as slang for money.