In Kultakeskus they call these maker's or 'my own' mark. If this product is found to be plated or ground wrong, it can be returned to the actual maker (= internal control mark).
The Kultakeskus responsibility mark was KKo/y from 1918 to 1932. Since 1933 they have used a lion-shaped mark. Due to Kultakeskus acquiring other precious metal manufacturing companies they also use additional responsibility and symbol marks. These can be found Tukes register.
1 = Reino Malin until ~1975, Seppo Ollikka ~1975–1980s
B = Pekka Salmi
C = Konsta Saari
H = Esko Hietamies
J = Risto Linberg 1960s
P = Esko Viitamäki
V = Eino Laakso, Ville Laakso
v (sideways) = Markku Laulaja ~1978-2008
W = Olavi Lehtinen
X = Pena (Pentti) Niinikoski
Z = Heikki Kajander
UNIDENTIFIED
The following marks have also been used:
2, 3, 4, 5, 6, 7, 8, 9, 22
G, I, L, N, O, R, S, U, Y, Ö, Å
2
N
R
U