help on age of button

[pro778]

I'm trying to find out the age of this button. It is a one piece flat button, with a bump out in the front of it, where the shank was soldered into the button. The only thing I can make out on the back is LONDON.
Thanks!

 

[vayank54]

It's a civilian flat button and dates 1790's to about 1830. It looks like the shank was smashed into the button so I think the bump on the front was caused by that. If you could make out any more of the backmark that might help date it a bit better.