A unique silver Thracian coin form the 5th century BC was presented in Bulgaria's city of Plovdiv.

The coin was unique because it was minted during the ruling of the Thracian king Sitalk. Up to now historians believed that coins were not minted during Sitalk’s reign, Focus news agency reported.

The coin weighted 3.7 gr and had its diametre was17 mm.

A horseman and some syllables could be seen on the head of the coin, Focus said. Acording to sources Sitalk had a 50 000 horsemen cavalry. An eagle holding a snake was prepresented on the tail of the coin.

Numismatist Dimitar Kostov said this was the first of its kind coin to be found in Bulgaria.

The price of the coin could reach 50 000 to 60 000 euro in an auction.