[endthematrix]

During the early 1970s, the price of copper rose to a point where the penny almost contained more than one cent's worth of copper. This led the Mint to test alternate metals, including aluminum and bronze-clad steel. Aluminum was chosen, and over 1.5 million of these were struck and ready for public release before ultimately being rejected. About a dozen aluminum cents are believed to still be in the hands of collectors,[citation needed] although they are now considered illegal, and are subject to seizure by the Secret Service. One aluminum cent was donated to the Smithsonian Institution.

http://en.wikipedia.org/wiki/Cent_(United_States_coin)

[JerseyJohn61]

Thanks for the info and link, Matrix.

Mea culpa, it was the 1974 cent and I had forgotten
about the large production strike that was eventually
rejected for circulation.

However, the original trial strikes numbered in the
hundreds and were distributed amongst the Washington
elite. When last I heard, many of the coins were
still unaccounted for....JJ61