Re: What if I don't want your gold or silver?
you underestimate the power and usefulness of money. money as much as anything else created modern civilization.
lets take your own hypothetical situation. what if you want someone to fix your generator and dont have the parts. but the guy with the parts has all the rice he needs. in fact you have nothing he needs at all. but he will take some silver or gold because he knows that can always be traded. now newport comes to you with an offer to buy some rice for silver. well now you are a motivated seller. you NEED the silver to get the generator parts, so newport offers you half a piece, you say no at least three, but he sticks by his guns cause he knows at least one other person who will sell him rice for silver, etc and eventually you settle for half a piece hoping someone else will come along and can get enough for the generator parts.
bartering only works when all parties have something the other party needs. when that is not the case, and both parties have different needs and different things to trade then the bartering economy collapses. thats why money was invented.
money is really a genius invention. and for reasons way too long to go into here, silver and gold will likely always be the basis of money, at least in the foreseeable future.