I just picked up one of these on Ebay that I thought looked interesting. I know that most are contemporary counterfeits and it was cheap. But the Machin Mills didn't start up until 1787. This coin is dated 1772. Link: http://s1262.photobucket.com/user/russ1709/media/_59_zps2dj6llan.jpg.html?sort=4&o=1 and: http://s1262.photobucket.com/user/russ1709/media/_60_zpsvhnw6bsu.jpg.html?sort=4&o=0
What makes you think its a Machin Mills ? Genuine Halfpennies dated 1772 are quite common, they get dug up here everyday. http://www.ebay.co.uk/sch/i.html?_f...2+Halfpenny.TRS0&_nkw=1772+Halfpenny&_sacat=0
"I know that most are contemporary counterfeits and it was cheap. But the Machin Mills didn't start up until 1787. This coin is dated 1772." I don't I just thought is was interesting. It might not even be real at all. And it was cheap. My limited research indicates the counteits were made during the Colonial Period and circulated.
What does it weigh? It doesn't appear to be a Machins piece and the contemporary counterfeits are significantly underweight compared to the real ones.
I would say that looks like a British halfpenny. It is low grade and has corrosion, but I don't see anything unusual about it.