Watch List notes:

George V, second coinage, trial sixpence, 1924, struck in gold, bare head l., rev. lion passant above crown, date 19 24 either side of crown (S.4024 [of the highest rarity]; W&R.430), in plastic holder, graded by NGC as Mint State 63, a tiny number 3 lightly engraved to the left of the lion in the reverse field by the Royal Mint, bold in strike with fully detailed face on the lion, and smooth surfaces glowing with gold lustre, a famous off-metal piece of great rarity
£15,000-17,500