I can not find this coin in the catalogue. How can help me ?
greetings
Jan
On top of that, welcome to numista, where you'll find a lot of knowledgeable people, who can help you a lot, if you read the forum policy before posting…..
The letter ɵ is actually called “fita”, derived from Greek theta, and mostly prounced as “f” in old russian, but also sometimes as “t” (because russian doesn't have the “th” sound). Eventually replaced by ф (f). Both ɵ and ф were often used concurrently, either based on the order in the word (first occurance would be fita, second ф), or on the original Greek words such as in ὀρθογραφία vs орѳографія. But there are more nuances and exceptions.
Boris Feodorovich. Kopek. Minted in Novgorod. #228 in the catalog of Grishin / Kleschinov.
It is one of the first dated Russian coins: the letters under the horseman are not clearly visible, but the only possible variant is "HPAI" (in all other dates the H letter is above the others). H means Novgorod Mint, PAI - year 7111 from the creation of the world, i.e. 1603 in modern calendar.