Great Britain KM# 808.1 / 808.2

Can someone explain the difference between these 2 coins?
I have a 1918 one and I can't say which type it is.
Thank you in advance.

Hi , I think it could be the type of finish that is on the coin. They produced a Bright finish and a Dark finish.
Hope that helps.

  I remember a topic from two years ago about darkened coins - I also remember it was using the gas Sodium Thiosulphate. Something about darkening them at the mint as they were similar to sovereigns in size, and the newly-issued farthings might be mistaken for the other coin.

https://en.numista.com/forum/topic5875.html