Removing niello

While searching on the .www under “removing niello,” I came across
your page. I am wondering if you can help me.

I have a Russian Orthodox niello ring. The black “niello” has slowly
been falling out of the past several years, and only about 50% of it
remains. I’d like to know how I can remove all of the black so at
least it looks consistent. While the black/silver contrast looks
nice, the all silver with the raised Slavonic lettering doesn’t look
bad either and is something I could live with. Alternately, I would
consider having it re-enameled (nielloed?) or maybe even a red
enamel would look really good as well.

Any advise? Can you direct me to where/how I can get the remaining
niello removed?

Yours truly,
Joseph Williams