Watch List notes:

THRACE. Maroneia. Circa 398/7-386/5 BC. Obol (Silver, 11.5 mm, 0.70 g, 12 h). Gorgoneion facing. Rev. Μ-Α-Ρ Bunch of grapes with tendril; all within incuse square. Schönert-Geiss 355 (V2/R2). Boldly struck and well-centered; struck on an oblong flan with a dark patina as found. Slightly rough surfaces, otherwise, about extremely fine.
From the "Collection sans Pareille" of Ancient Greek Fractions, ex Münzen und Medaillen FPL 505, November-December 1987, 60 and Giessener Münzhandlung 36, 8 April 1987, 55.