The catalogue contains two different versions of the UK 3 pence coin but both versions have a 1920 coin. How do you tell the difference because they seem identical to me? I realise the silver content is different but wanted to confirm whether they are otherwise identical and thus impossible to differentiate
If you look closely at the details, you'll see that the 2nd issue is very slightly thicker (to accommodate the change in composition). There is also a difference in the sound they make. The .925 would sound like a 1919 and the .050 would sound like a 1921. Other than x-ray fluorescence to get the exact composition these are probably your best bet for differentiating them.
