Watch List notes:

MACEDON. Skione. Circa 424 BC. Obol (Silver, 7 mm, 0.47 g, 8 h). Head of youthful Protesilaos to right, wearing tainia. Rev. [Σ-Κ-Ι] Corinthian helmet to right; all within shallow incuse square. Skioni 123ιε (this coin). Traité II, 4, 1022 = pl. CCCXVII, 17 (same dies). Clear and toned. Very fine.
From the "Collection sans Pareille" of Ancient Greek Fractions and from the collections of Leo Mildenberg and C. S. Bement, Naville VI, 28 January 1924, 650.