Watch List notes:

COINS, EUROPEAN TERRITORIES, ISLE OF MAN James Stanley, 10th Earl of Derby (1702-1736), Silver Pattern Penny, 1723, by William Wood, Stanley crest, the eagle with child upon cap of maintenance, frosted cap, date below, rev Triune (Pr 4; S -; KM Pn16). Good fine, extremely rare.
ex Dr R Caine collection of the Isle of Man, Spink Auction 145, 14 July 2000, lot 2694
The low grade is interesting. It is most likely a pocket piece and spent a long time carried by its owner

Estimate: £1000-1500