The stigma of the master Lindman Sven Peter - Leningrad - initials "Lindman"

G OkerblomThe stamp of the master Gustav Magnus Okerblom - Leningrad - initials "G Okerblom"

KeibelClaymo Master Cabel Otto Samuel - Leningrad - initials of Keibel.

I:DUCMr. Duke Jean Jacques - Leningrad - initials I:DUC

R.TAVASTClaymo Master Tawast Roman - Tallinn - R.TAVAST - 1920-1940.

ПЛАТИНОПРИБОРClaymo PLATINOPROBOR - Moscow

П.ЧУКСАНОВЪClaymo Master Chuksanov Petr Arcadjevic - Leningrad - initials of P. Chuksanovac - 1898 - after 1908