Groat, Which Mint?

bronzemat

Picked up this Henry VI Groat, but I admit medievals are not a specialty of mine but I do enjoy them.

I was just wondering if anyone can tell me which mint this Groat it? I am pretty sure it's a first reign. Also it weighs 4.03g, a bit heaver then all others I have seen.

Thanks for any help.

BS

It's from Edward III and London mint.