Hi Atlas -
Around the city of Moscow there was a plethora of Niello and enamel workshops that worked from simple to excellent. My personal opinion - which is based on numerous real pieces is: after Niello had come into fashion but not every manufacturer wanted or could build their own Niello production -it was simply bought at the already existing workshops. Advantage: increased turnover for the Niello makers - increased sales for the non Niello makers.
Gustav Klingert is wellknown and famous as top enamel maker (see other threads on the forum) but not as Niello maker. Please distinguish between maker and seller! Your shown Niello napkin ring is of very good quality and marked with the authentic Klingert punch and the assay mark for this time frame. I believe in some sort of a cooperation. Unfortunately most of the Niello artists are unknown by name - we only know the vendors. The same you can say about many/most of the Moscow enamel artist and the icon painters. They remain hidden in anonymity and unfortunately we will never know who they were.
Congratulation to a very nice napkin ring!
Here some similar napkin rings with markant architecture views from my collection - I know the seller but not the maker....
Ivanov
![Image](https://abload.de/img/iwanovmaksim01bgzs3c.jpg)
Neumelov
![Image](https://abload.de/img/neumelovn.p.01bnps9w.jpg)
Unknown
Regards
Goldstein