BBC News: How much is a penny worth?
Rising metal prices could mean that United States one cent coins become worth more as metal than for their face value. Could that ever happen in the UK? The soaring prices of zinc and copper have prompted fears in the US over the future of its one cent coin. If the scrap value of the coin, which is made from these two metals, exceeds its nominal value then it becomes an unsustainable arrangement. It would be like selling fivers for £4.95. So what will happen if the price of these metals continues to accelerate upwards? And could anything similar happen to coins in the UK?
Yes, it could happen here, is the answer from Lawrence Chard, of Chard coin dealers. And that's not just speculation because it's happened before. "Copper" coins in the UK will not be affected directly by increases in zinc and copper - because the one and two pence pieces are made from copper-plated steel.
Gold hasn't been used in UK coins since sometime after World War I, and silver was discontinued in 1947, copper could be next to go. I didn't know that there was more copper in a UK 10 pence or 5 pence coin (as cupro-nickel, 75% copper and 25% nickel) than in a penny or 2 pence piece. Maybe that's why those silver-coloured coins got smaller in the 1990s. UK "coppers" minted after 1992 are the steel versions and can be magnetised, before that they were mostly bronze.