What's special is that it's made to be exactly 1.0gram. Many children in Japanese school still use 1 yen coins as an excellent way of weight comparsion.
My partial coin collection http://www.omnicoin.com/collection/gxseries
My numismatics articles and collection: http://www.gxseries.com/numis/numis_index.htm
Regularly updated at least once a month.
My numismatics articles and collection: http://www.gxseries.com/numis/numis_index.htm
Regularly updated at least once a month.


















