Watch List notes:

BRITISH COINS, Richard III, Silver Penny, Durham mint, Bishop Sherwood issue, facing crowned bust of King with S on breast, initial mark lis, rev D at centre over long cross pattée, trefoil of pellets in angles, legend and beaded circles surrounding, 0.78g (N 1687; S 2169). A little short of flan, about very fine, toned and rare, superior to Spink plate coin.
ex Spink Numismatic Circular, 1942, item 16404 (as York? and "as struck"), sold for £2/5/-

Estimate: £400-600