Claymo Master Moskov Yakov - Leningrad - initials of "I-M" - about 1,800.
Similar hallmarks
ВШClaymo Master Shevikov Vasily Ekimov - Kostrom - initials of the HS - 1794-1795.
ЯАClaymo of an unknown master of Moscow - initials of the YA - 1740.
А-Ф ПKlemo Master Petrov Fedor - Moscow - initials A-FP - 1759-1784.
ВСClaymo Master Savel Vassili Piemenov - Costrom - Initiators of Air Force - 1849-1874
А-А КClaymo Master Kosyrev Alexei - Moscow - initials of A-A C
Я-МClaymo Master of the Yakov Semenov Maslennikov - Moscow - initials of the Y-M - 1756-1790.