Probably Ladislaus Jarosinski.
For Jarosinski merging history see here:
http://www.925-1000.com/forum/viewtopic ... oin#p91639
Qrt.S wrote:The first mark is the "maker's mark/logo" for Koruteollisuus Tillander Oy (Jewellery Industry Tillander Ltd) in Helsinki 1946-1973. The rest you already know. A very typical and popular product of Tillander industries in those days.
See Cesa 1882 at: viewtopic.php?f=38&t=27003&p=131908&hilit=cesa#p131908