1826 UK Farthing Chop-mark???

I was looking at this very decent 1826 Farthing and the shield on the reverse caught my eye right away.  It seems like I see something there like a number three or eight!!!  I see no other obvious damage on either side of the coin.  That's what's got me puzzled, what ever it is, it looks to deliberate to be post mint damage.  Especially since it's nicely confined within the outlines of the shield!!!  I hope the pics are good enough for y'all to help me figure this curiosity out!!!

Just to let you know I have sent a picture of this coin to a friend in England for a possible explanation and will let you know once I have received the info.

As a farthing collector I have never seen anything like this before.

Nice coin

Thanks!!!!  I look forward to hearing his opinion!!!

Here is what he has said

(In terms of the 1826 farthing, that is definitely post mint damage. The coin has been counterstruck, leading to that effect. If you imageine the die would be a negative impression of the coin, so therefore you would not get the raised areas around the countermark where the metal has been displaced. Because to get this effect you would have to add metal to a die.)

I hope this helps