Akanthos, Macedonia. AR tetradrachm. ca. 430-390 BC. 14.51g.

Lion right, attacking bull kneeling left, its head thrown back, swastika above. 
AKA-N-QIO-N around a granulated quadripartite square, all within a larger incuse square.

The swastika symbol is not in Desneux, AMNG, Traité, SNG ANS etc.
Info added: There are thirteen examples of coins with this 
symbol on CoinArchives, sold in auctions going back to 2003. 

With permission of Ira & Larry Goldberg Coins & Collectibles, auction 42, lot 19, Sept. 2007.

Goldberg_42_19.txt