Then it's a farthing: http://www.predecimal.com/britishcoinsiden...ntification.htm Despite what your wife may say, size does matter and when identifying coins millimetres count. If it looks average, like this one: http://www.predecimal.com/forsale/7/farthing1843.jpg Then it should be worth £2-£4. If it's worse, it may struggle for 50p, and of course if it's better it'll be worth more.