Tom Burton asked me to provide a full ID and a valuation on this early milled silver coin of William III. Tom thought it could be a shilling but said it measured 21mm in diameter so it must be a sixpence.
On the obverse is the first bust of William III and as it does not have a letter underneath it the coin must have been struck at London. On the reverse are large crowns over the shields, the early harp in the Irish shield and the date, 1696, is positioned either side of the English shield. Sixpences of this type are listed as number 3520 in the Standard Catalogue.
Sixpences of William III are the most common early milled coins found by detectorists. There are several scarce and rare varieties but Tom’s find isn’t one of them.
The obverse of this coin would grade about VF but the reverse isn’t as good. It doesn’t display as much wear as on most that turn up as detecting finds but it has a significant defect: there is a striking crack starting below the bust of King William. It’s certainly very unusual for a coin of William III to have a striking crack but this will reduce its possible commercial value. As it stands, I would price it no higher than £25 – £30.