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Hi Ed, A shrunken coin has the same mass and density as before. I've submitted samples metallurgists for analysis, but I don't have the results as yet. The metal does become work hardened. The coin gets thicker in the process so that the overall volume remains constant. This effect can be seen in Figure 4 of the ErrorWorldNews article: Because the electrical conductivity is highest in the pure copper center, the shrinking forces are strongest in the center layer of clad coins. This results in the less conductive outer clad layers getting pulled along for the ride as the coin's center shrinks radially and teh edge of the coin assumes an "oreo cookie" profile. In some cases the cladding is has hidden manufacturing defects and imperfect bonding. This causes partial separation of the cladding layers, and the resulting force imbalances cause dramatic distortions in the shape of the shrunken coin - see: Thanks for visiting! -- Bert --
: Saw the article in popsci and it left me with many questions.
: First, does the shrinking change the molecular structure of the material
: shrunk. Is it that just the same amount of material is there and just
: thicker or what? Does it weigh the same? Is there a change in hardness?
: Is the clad metal more tightly bonded? These are just a few of the many
: questions that immediately occur.
: Thanks for bringing this to my attention and I guess I have to add your
: BB to the list I follow.
: Ed
:
http://205.243.100.155/photos/Shrunken_Coins1.PDF
http://205.243.100.155/frames/mutantKYr.jpg
http://205.243.100.155/frames/mutantKYf.jpg
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