Claymo of unknown master Riga - GTB initials - 1879.

С.Т.В.Claymo of unknown master Riga - initials of S.T.V. - 1856.

Л.Ф.Г.Claymo of an unknown master of Odessa - initials of L.F.G.

CMSClaymo Master Charles Magnus - Leningrad - initials of CMS 1830-1849

C-M-SClaymo Master of Steel Carl Magnus - Leningrad - initials of C-M-S - 1830-1849

CRHKlemo Master Hermann Robert Hugo - Tartu - initials of CRH - 1853-1886.

C-F-B-BClaymo Master Bradenberg Carl Frederick - Leningrad - initials C-F-B-B