zinc prices? from Australian website today:
There are 160 pennies - also known as a 1c coin - in a pound, worth a face value of $US1.60. With each penny made of 97.5 per cent zinc and 2.5 per cent copper, based on current prices the metal value is worth about $US1.36.
Therefore another 25c a pound rise in zinc, or about $US551 a tonne, would see the metal value of the US penny worth more than the monetary value.
-interesting