a green blob when dug, this is after a short electrolysis to get the details, Brit., Canada or Spain. coin is medal orientation. hit solid 51 on ATPro at shallow depth. FMERG put his coil over it and got it as a Jeff ID on his Minelab SEPro
That's really cool, it's a low denomination Spanish copper coin of what looks like King Carlos III, likely a Maravedis coin from 1759-1788. Or it cold be British, hard to tell if that's the British shield or the Spanish one, but it looks like the Spanish monarch Carlos III.
There are contemporary counterfeits of George lll spade guinea gold coins that were gold plated copper; they were used as gaming tokens etc (poker chips)
I think that's what you might have