The last letter of their mark series' are what Auran Kultasepät called 'kretsileima'. The closest translation of this is 'filings mark', specifically the waste filings or rubbish left after making a metal object. They were originally associated with being a mark for identifying the responsibility for shoddy and bad work rather than good; an internal quality or control mark if you like. Only later were these given 'master'-mark status.

 

n = Veikko Nuutinen (1941-1954)

 

aksx
x = Matti Lehto (n.1950-1989)

 

aurae
e = Raimo Roine (1946-1990)

 

risto nordling
m = Risto Nordling

 

A = Armas Ahla

 

A = Anna-Mari Autio (1980s)

 

B = Aimo Järvinen

 

C = Reino Lehtinen

 

E = Aulis Alin

 

antero kivi
K = Antero Kivi

 

eero lehtonen
L = Eero Lehtonen

 

aksp
P = Kauko Stranden (1950s)

 

P = Pertti Alin (1975-1990s)

 

R = Antero Rimmanen

 

sulevi ojala
U = Sulevi Ojala

 

harri ahokas
Ä = Matti Salonen

 

Å = Harri Ahokas

  

UNKNOWN

M, F, J, G, O, H