This commemorative medallion was advertised as being made of an alloy of 1/3 rhodium and 2/3 nickel. Very unlikely, but I haven't had it tested yet, so I'm not going to make a definitive statement yet.
Source: eBay seller alpha-omegaman
Contributor: Theodore Gray
Acquired: 11 March, 2009
Text Updated: 12 March, 2009