Image rights: wildwinds.com

Tanagra (?), Boeotia, AR trihemiobol

     Tanagra (?), Boeotia, AR trihemiobol, (1.14g) early 5th century
     BC, 
Boeotian shield 
Incuse square containing wheel of four spokes. 
Cf. BMC (Tanagra(?)) 18-21 for an obol. 

The types obviously influenced by the contemporary 
Turtle / Skew coinage of Aegina. 
Rare.