Koinon of Karthaea on Keos, Cyclades. End of 4th Century BC. AE14mm (2.24 gm). 

Y-X, head of Aristaeus right
K-E, bunch of grapes on vine. 

Papageorgiadou-Banis, The Coinage of Kea, Series I; BMC Crete -; 
SNG Cop 626. 
Near VF, dark brown patina. Very rare. ($250)

This is the only recorded specimen with the letters on the obverse visible.

Sale: CNG 60, Lot: 592. Estimate $250. 
Closing Date: Wednesday, 22 May 2002. 
Sold For $475.

With permission of cngcoins.com