William IV 1836 Sovereign N of ANNO in shield error, extremely rare

William IV (1830-37), gold Sovereign, 1836, variety with letter N struck additionally in the shield on the reverse, second bare head right, nose points to second I in legend with flat top ear, W.W. incuse on truncation, GULIELMUS IIII D: G: BRITANNIAR: REX F: D: toothed border around rim both sides,rev.crowned quartered shield of arms in frame, N struck in lower left quarter, legend ANNO 1836 below, weight 7.93g (Bentley 31; Hill 20A R4; M.C.E.493; Bull EGC 1030 R4; S.3829B).Toned good fine and extremely rare.

The Latin legends translates on obverse as "William IV by the Grace of God, King of the Britains, Defender of the Faith," and on the reverse "In the year 1836."

We previously handled one of these coins with a Royal Mint letter dated 27^th January 1989 from then Librarian and Curator G P Dyer which detailed that the coin previously sold had been shown to the Chief Engraver of that time, who believed the letter N could only have been placed in the shield deliberately as it was too firmly entered to be so off-target and even if a rebound from trying to repair one of the Ns of ANNO. The letter goes on to say that deliberate additions to dies to mark them out are known from the later period where the Ansell Sovereign has an extra raised line on the hair fillet and the 1863 Sovereign with 827 instead of WW on the neck indicates a gold bar that was used. However the explanation for an N at this earlier period does not show in the records and this was the first 1836 Sovereign seen on Royal Mint record. The only intriguing nugget of extra information the letter gives and for the first time noted online here (no doubt to add as a footnote in a future revision of the Marsh book) is that of the few tools, matrices and dies that survive from the time of William IV there is an obverse and reverse matrix from 1832 that have a letter N stamped on the upper surface well away from the design. There is also a reverse punch with 183- where the two has been removed and a badly formed mark like an unbarred H in its place. There are also some other surviving tools that have letters such as G or H on their surfaces, but alas there is no record or clue as to what any of this signified.