Watch List notes:

Thraco-Macedonian Region. Uncertain mint, Olynthos (?). Circa 500 BC. Tetradrachm (Silver, 25 mm, 17.03 g, 6 h). Charioteer driving slow quadriga to right; above, large pellet. Rev. Large quadripartite incuse square containing, at the center, an eagle flying to left within a small incuse square. ACGC 475. Asyut 212. BMFA 612. H. A. Cahn, "Olynthus" and Syracuse, Studies Thompson, Variety B and pl. 2, 3. SNG ANS 463. Very rare. Struck on a broad flan and surely one of the finest of the few examples known. Good very fine.
From the Cinquantenaire Collection, Switzerland, and from the Prospero Collection, New York Sale XXVII, 4 January 2012, 263, acquired privately from G. Müller on 15 October 1985.

Usually ascribed to Olynthos, Cahn makes a convincing case to exclude that theory due to a complete lack of evidence. In any case, coins of this type must have been exported as bullion to Sicily since it is absolutely certain that they inspired the types of the first issues of Syracuse.