Heraia, Arkadia, AR trihemiobol, 1.46 ca. 490.450 BC. 

Helmeted head of Athena left.
ERA downwards to right of three Es (mark of value) arranged two 
back to back and one above, two ivy leaves in left field.

BCD (LHS sale) 1359 (this coin); Imhoof, MG 209;

With permission of LHS Numismatik AG, May 2006.
Estimate: 450 SFr.
Extremely rare.