Hey look, my interest in the one-cent piece is timely: apparently there is a bill being introduced that would make the penny obsolete. I read it in today's headlines.
I hadn't really thought about the fact that a nickel is actually mostly copper, and that particular states would benefit from eliminating the penny because of copper mining.
US five-cent nickel
composition: 75% copper, 25% nickel
mass: 5.000 grams
volume: .5609 cc
value of metal: $0.06669
So, as with the copper penny of pre-1982, the metal in a nickel appears to be worth more than the nickel itself. Does this mean it would be better for the economy to use five (post-1982) pennies instead of a nickel? Or does the production cost of making five pennies (as opposed to a single nickel) make this equally expensive?
The CNN article states that the total cost of producing a penny is $0.014. Using my calculation that a modern-day penny contains $0.00884 of metal, we can conclude that the cost of minting a coin is about $0.0052. Five pennies would cost 5 x $0.014 = $0.070. If we assume that minting a penny and minting a nickel cost the same, a nickel's total cost to the US Mint would be $0.06669 + $0.0052 = $0.072. Five cents in coin costs the US Mint about seven cents if you're using pennies, but it costs slightly more if you're using a nickel.
(If you're interested in this penny debate, check this out.)