Gold into Silver

We watch TV in French here in Vitry - so please come and visit us, but don't come hoping to catch your favourite English soap - we ain't got it!
But being an Englishman I have a learned understanding of the language so that my understanding is not intuitive. I suspect what I am about to relate would appear daft to a Frenchman, but to me, who had to change it into English in my brain, it is clear as precious metal!
You have probably seen adverts in the UK for changing your gold into cash ("postal gold" I think). Well that's fair enough. But here it they say "change your gold into money". Now you may recall your French education where money in French is the same as silver. So here the slogan is:

D'or entre argent!

or to put it another way:

From Gold into Silver

Now why would anyone want to do that?