This should put pressure on Copper Bullion coins http://articles.chicagotribune.com/...20_1_rare-penny-coin-dealer-heritage-auctions
I don't see why you would think so. The only relation that they would have is that they both happen to be made of copper... When a 1913 Liberty Nickel sells does it put pressure on Nickel prices?
At least the Chicago Tribune article eventually mentioned the reason for the silver plug was to increase the value of the metal content. Every other article I've seen (including the press release quoting the head of the auction house (Heritage) who should have know better) just stated that the silver plug was to increase weight. The silver plug wasn't added to increase weight (since the density of sliver and copper aren't that much different)), but was aded to increase the value of the metal in the coins. In 1792, one cent of pure copper would have required a 1¢ coin to be about the size of a silver dollar.
The silver was not added to raise the weight, and it was not added to raise the intrinsic value, it was added to KEEP the intrinsic value at one cent while LOWERING the weight. The cent as originally authorized already had a full cent intrinsic value, but it was going to weigh 264 grains (17.6 grams or about twice as much as the post 1795 large cents or 50% more than the current half dollar.) By adding the silver center they keep the intrinsic value at one cent but were able to lower the weight to 69 grains (4.5 grams or a little less than the current nickel) They decided it was too much trouble though and they just decided to lower the weight and produce the coin with an intrinsic value less than face and use the resulting seneiorage profits from the copper coinage to pay for the expenses of the mint and allow for free coinage of gold and silver.
