  Field's metal. 
Field's metal is a low-melting-point alloy, which will melt in hot water.  It's named after Simon Quellen Field, who runs scitoys.com, a great site for educational and scientific toys and kits.  He sells this alloy in the form of lengths of metal-filled plastic tubing, which you can easily melt or cut it out of. 
Source: Simon Quellen Field 
Contributor: Simon Quellen Field 
Acquired: 13 February, 2007 
Text Updated: 14 February, 2007 
Price: Donated 
Size: 5" 
Composition: InBiSn
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