Watch List notes:

ATTICA. Athens. Circa 545-525/15 BC. Obol (Silver, 8.5 mm, 0.77 g), from the so-called Wappenmünzen series. Wheel with central boss, four spokes and struts. Rev. Rough incuse square. Agora 4. Nomos 13, 2016, 181 (same dies). Seltman pl. IV, ν. SNG Soutzos 658. Svoronos pl. 1, 60 (same dies). Clearly struck and with an attractive grey patina. About extremely fine.
From the "Collection sans Pareille" of Ancient Greek Fractions and from that of L. Mildenberg.