Aetna, Sicily, AR tetradrachm. 17.23 gr, 26mm. 476-431 BC. 

Obv: AITNAION, head of the satyr Silenos, bald and bearded,
 right, with pointed horse’s ear, and wearing a wreath of 
ivy wreath, beetle below. 

Rev: Zeus Aitnaios seated right on ornamented throne 
covered with a panther’s skin, himation draped over 
his left shoulder and arm, holding thunderbolt in 
extended left hand and a knotted vine staff bent into 
a crook at the top in his right hand; to right a 
pine tree with an eagle perched on top.

The Aetna Tetradrachm is one of the rarest Greek coins 
known, and the Collection Lucien de Hirsch, Bibliothèque royale de Belgique, Brussels museum has placed a conservative estimate of its value at more than $3 million. This Aetna Tetradrachm is the only one of its series ever discovered.

Hill, Coins of Ancient Sicily, P. 74 and Pl. 4, 13.

Courtesy of collection Lucien de Hirsch, Bibliothèque royale de 
Belgique, Brussels