So you got a 20p coin undated lucky you. Question what do you do with it keep it or sell it. Now there are 200,000 out there so whats the value of it? It depends on what condition its in and who whants it and how much they want to pay for it. Mint £20-£30 Worn £5-£10. This is just my thoughts on it as there are so many. Also the countless fakes on the market now because if you see the 20 pence coins with the date on they are so light its so easy for the fakers to cover it up. So if you are buying one beware of the fakes and if you are selling one good luck with hitting the jack pot. One last thing would you really pay £8,000 pounds for one or buy real gold coins which vaule normaly goes up.