This is one of the commoner issues of James I shillings, though most private and institutional collections have at most a few specimens arranged by the types first noted by Hawkins in 1841 – Plain reverse, plumes reverse, maybe a contracted IACOB legend and the other abbreviations in MAG BRIT FRA and HIB.
This note presents a die study of these shillings showing the potential for mining on-line auction catalogue archives, for which Noonans (formerly Dix Noonan Webb), London Coins and Noble Numismatics (Australia) are thanked. Images of 84 specimens have been found and have revealed 50 different obverse dies and 63 reverse dies. The relatively small number of die duplicates in the sample suggests that there will be over 100 obverse dies and even more reverse dies to be found.
Comparison with the previous note looking at mintmark Rose shillings (link) and the amount of silver presented at the respective Pyx trials suggests that it might be possible to estimate the number of dies used to strike shillings for each initial mark through the whole reign of James I and into the Tower issues of Charles I.