Watch List notes:

ROMAN & BYZANTINE COINS

Constans II, with Constantine IV, Heraclius and Tiberius, 641-668. Hexagram (Silver, 20mm, 6.60 g 7), Constantinople, 666-668. ...]AVgU Bust of Constans II facing with long beard, wearing crown with plume and holding a globus cruciger in his right hand. Rev. Three figures standing facing, from left Tiberius, Constantine IV and Heraclius, each wears a crown bearing a cross and a chlamys, and each holds a globus cruciger in his right hand; to right, S. DOC -. MIB -. SB -. Of the greatest rarity, one of apparently two known examples, and unpublished. A coin of the greatest historic interest, toned and well struck. Struck on a ragged flan and uncleaned as found, otherwise, nearly extremely fine.

This astounding novum must have been issued very late in the reign of Constans II: its design is basically the same as that of the late solidi, DOC 42-43 and MIB 41-42, and it must have been struck at the same time. Its extreme rarity indicates that it must have only been struck in very small numbers.