| | |   Japanese coin. I know I brought back a handful of these last time I was in Japan, but I can't find any of them.  Fortunately Ed had some, and it's not like they're actually worth anything, which is why they are made of aluminum in the first place.  Reader Lawrence Spiwak told me an interesting fact: A one yen coin is exactly two cm in diameter, and weighs exactly one gram.  I've verified this to 5 decimal places with my analytic balance, so I know it's true.
 Source: Japan
 Contributor: Ed Pegg Jr
 Acquired: 6 September, 2002
 Text Updated: 9 April, 2009
 Price: Donated
 Size: 0.5"
 Purity: >90%
 Sample Group: Coins
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