1799 Halfpenny - Copper Proof Or Unc Circulation Coin?

that's a very nice piece.
I'd be wondering if it was a restrike, possibly using original dies.
There are stories that the 1797 series was restruck upto 1848, so if that is true, then something similar might have happenned with the 1799 coinage.
I'd be in no hurry to let that one out of my sight, and I'd be looking at evry 1799 half-d, or pic thereof, that I could lay my hands on.
Peter in Oz

Here's what I have. First of all the counterfeiting of coppers went rampant in the late 1700's, it was reported by 1789 an average 2 out of 3 half-d were counterfeit. That prompted the coinage reform and appearance of the "cartwheel" design. In 1797 they issued cartwheel 2d and 1d but excluded half-d's for the reason that it would drive out all the fakes out of circulation but wouldn't satisfy the demand. Still there was public demand for legal half-d's, so in 1798 the contract on striking halves and farthings dated 1799 was effected. The price of copper though had risen, so the cartwheel design didn't work anymore. They switched to more conventional design with smaller size. For this reason the coins were not popular with the public first. Halves were minted at Soho for a number of years, all dated 1799, till in 1806 they redesigned both sides.
What Peter refers to is the cartwheel design dated 1797, both 2d and 1d; they issued pretty much all proofs up to as late as 1830 (they refer to it as "late Soho"). And in 1848 W.J. Taylor bought the dies and produces restrikes for collectors - those are not considered the official coinage (but good luck distinguishing them!).
Your coin, Jeff, looks genuine to me, and it could be a proof. Here's another example of the net: