You are right about the awful way they meddle with the value of currencies. But you might wanna look more into the precious metals opinion of them being undervaluated. Gold and silver are in fact not "rare" the cost often times many times more than another way rarer element. The people in charge of the markets just make shure there is a steady availibility to keep the price just right. and every now and then give it a little boost by shortening supplies.