Watch List notes:

Thrace, Byzantion in alliance with Kalchedon Æ 25mm. 3rd century BC. Veiled head of Demeter to right / Poseidon seated to right, holding aphlaston and trident; ΒΥΞΑNTI to right, ΚΑΛΧΑΔ to left, monogram in inner right field. SNG BM Black Sea 82-3 var. (rev. legend); HGC 3.2, 1428. 9.87g, 25mm, 12h.

Good Very Fine. Scarce with this legend.

From the inventory of a UK dealer.