I have recently spent a lot of time adding the George III 1797 and 1805/6 pattern, proof and restrike penny varieties to my varieties website. I thought it needed doing because the pictures in Peck are small, black & white and very low resolution , making it hard to identify individual varieties and check the minute details such as the number of gunports on the ship. I've been taking photographs from auction sites but still need photos of some varieties to complete the task.
While I was doing this, I discovered that my specimen of 1806 "P1326" is, in fact, an unrecorded (as far as I know) die-pairing. Peck, on page 366, states that the only occurrence of the 1806 proof penny with imperfect date figures (1 and 0) is in die-pairing KP31, paired with a reverse featuring a ship with 3 stays from the foremast to the bowsprit, being struck in Gilt (P1325), Bronzed copper (P1326) and Copper (P1327).
However, the penny that I bought from London Coins auction in 2010 (lot 1544) as a Peck 1326 has the obverse with imperfect date figures described above but the reverse of KP30 which Peck records uniquely on P1322, 1323 and 1324 and has only 2 stays from the foremast to the bowsprit and, importantly, a very conspicuous die flaw from the second A of BRITANNIA to the border.
I don't know whether this has been noticed and/or recorded before, or how important it is but it is interesting (to me, at least !)
All other specimens of P1325-7 that I have seen have the die-pairing documented by Peck.
Maybe some of you copper experts can comment ?