Many opinions have been made regarding the date of the production of the koson coins.
The researchers who read the monogram in connection with Brutus dated them in 42 BC. Those who saw the letters of the monogram reading OLBIA and this city as producer, connected them with a Scythian ruler from around 40 BC.
Those who consider that the coins were minted in the name of king Cotiso, the one mentioned by the ancient sources, date them in the time of Augustus, towards 30 – 20 BC.
An extremely interesting theory considers that all the kosons are.... medieval forgeries. Initially, in 1973 Monedele geto-dacilor, Constantin Preda considered these coins as ancient, but he later revised his opinion:Marcus Iunius Brutus