Affects of alloy change on host coins has been noticed by collectors of U.S. pieces - machines are adjusted to suit whichever.... 1982 saw the change from a 95% Copper one cent coins to Copper-plated-Zinc pieces. Collectors prefer elongated U.S. cents to be on cents of the old composition since the newer Copper-plated-Zinc pieces are very prone to tarnishing.

The G.B. 1 Penny coins changed in composition from Bronze to Copper-plated-Steel in 1992. I have elongates in each of these compositions and as yet I can see no difference for anyone to have a preference either way. Something else that I notice about my pieces is the variation in length, there doesn't seem to be any connection between composition and size (length) though. The length variation, I therefore assume must all be down to the setting of the rollers.