first of all, dump the idea of putting your investments to banks, the returns are not big as any other investments, even for a long term value, banks are way to lame. in gold and silver, uhm i think it is different in such a way that those precious stone' value are dictated how people demands for it, how investors are reacting on the current value, just like diamonds, which its value are just a product of a good marketing strategy, it is how the market perceived its value.
Remember 9/11 terrorist attacks in USA in 2001 and stock markets crash 2008 when DOW Jones went to 6000.
In such events, Gold and Silver gives high profits but banks and other investments are hopeless as the economy comes to an halt. For 4 days no plane/aircraft flew in USA. Airports were shut down.