Coinflation

I vaguely remember when pennies became worth less than the copper they contained; via MR, the same condition has spread to the nickel and beyond:

US five cent coins contain over 7 cents worth of raw material as of this afternoon, mostly copper and of course, nickel. If there is inflation, the prices of metal will increase, and the coin will have 8, 9, 10 cents worth of metal. Pre-1965 dimes contain over $2.42 of metal today, while pre-1965 quarters have over $6 worth of metal.

I wonder what they did to dimes and quarters after 1965, and whether the same is in store for the nickel. (While the penny, of course, should just be abolished.)