Eastern Celts, Boii. AV 1/8 stater. 10mm, 0.7 g.

Bulged, convex shape, traces of a head ?
Concave divided into twelve sections by two vertical  
and three horizontal lines. 

Janków type B1; Rudnicki 111-113

Found in Kruszyn, Poland.
Courtesy of Marcin Rudnicki.