Watch List notes:

BRITISH COINS, Charles I, Silver Halfcrown, Tower mint, group IV, king on horseback left with raised sword, sash flowing from shoulder and waist, initial mark triangle in circle (1641-1643) both sides, rev large quartered oval shield of arms with garnish, 15.39g (N 2214; S 2779). Attractive old tone, flan a little irregular with minor obverse metal flaws to surface, otherwise nearly very fine, reverse better.
from the David Sellwood collection

Estimate: £150-200