Unknown Maker

[Joanies]

Could anyone please help me identify this maker ?

[Qrt.S]

The hallmark tells us that the box is made before 1882. In St. Peterburg worked Robert Yakolevich Kohun/Kochun . He punched Cyrillic PK (Latin RK) in an oval frame 1842-1883.

[Qrt.S]

Found some more information:
He was an Englishman who came to St. P in 1815 and co-operated with Nichols & Plinke. He founded the company as a companion to Carl Nichols in 1829

[Joanies]

Wow, thank you so much for the info ! It is truly much appreciated :)