In 1911, the German scholar Max von Bahrfeld wrote the first scientific study dedicated to the subject of the gold koson coins, and correctly identified these coins as Dacians, of one type with two subtypes, if they bore or not a monogram on the obverse.(source: Ponterio & Associates, August 2013 Chicago ANA World’s fair of money, the 13th of August 2013, no. 11050)
The monetary type was described in detail or in general by many researchers. Perhaps the most known is the following one:
The obverse is similar to the reverse of a Roman republican denarius, minted in 54 BC for Marcus Iunius Brutus: four men walk towards left; an accensus opens the way for a consul who is flanked on each side by a lector. On the obverse of the kosons, we find only three characters: the accenus is missing (the first from left on the original coin).(source: koson: Ponterio & Associates, August 2013 Chicago ANA World’s fair of money, the 13th of August 2013, no. 11050; denar Iunius Brutus: Ponterio & Associates, August 2014 Chicago ANA auction, the 5th of August 2014, no. 30183)
The reverse of the koson type coins is also inspired by a Roman republican denarius, of Q. Pomponius Rufus, from 70 BC. On the original Roman coin, an eagle with outspread wings is represented, towards left, with his head turned towards right, holding in his right claw a laurel wreath and sits with his left claw on a sceptre. The difference between the reverse of the kosons and the Roman denarius is the fact that on the Dacian coins, the eagle has his head turned towards left, and the letters and symbols on the Roman denarii were omitted.(source: koson: Ponterio & Associates, august 2013 Chicago ANA World’s fair of money, the 13th of August 2013, no. 11050; denariu Pomponius Rufus: Nomos, 1, 6 May 2009, no. 133)
About the eagle, it seems that it has several iconographic varieties.
The legend of the coins, namely KOΣΩN, written with Greek letters, can be transliterated as KOSON or COSON. The significance of this work is still unknown, various hypotheses being made until today: a proper noun, in nominative case, the name of the issuer (king) or even a common word, maybe abbreviated. In the classical Geto-Dacian civilisation, the Greek language was used by the elites in diplomacy also, and seems to have been known by some.
The presence or the absence of the monogram on the obverse has always been a criterium in dividing one unique type into two subtypes.
In 2000, it was considered that:
The idea is again sustained:
It has also been written that:
Other theories, like reading it O L B (Olbia) or that it might be read as Brutus, are uncertain.
It has been noticed that the coins without monogram have a much raw style than that of the coins with monogram, therefore indicating two different moments of production or maybe two different engravers.Koson without monogram (source: Teutoburger Münzauktion, 77, the 6th of September 2013, no. 1003)