Help with maintaining oxidisation in recess

[Susie]

Happy New Year everyone.
I would really like some advice on how to maintain some oxidisation in the recesses of a silver ring.
I made some rings with a deep laser hallmark on the outside and have tried various methods of making it stand out.
Using platinol and also using some stamping ink. Can you advise on the best way to keep the black colour? I'm attaching a photo to show you the ring.
I wondered if there was a liquid sealant i could paint into the recess? The edges of the hallmark are a bit sharp, so can't really use a cloth to rub a waxy sealant into it, so is there a liquid?
Thanks so much for your help. I made a ring for a member of family, and the blank ink i used has already come off. I know this can be googled, but i'd rather get advice from the experts.
sue

[Susie]

Also, just to say I did read the thread on her on how to keep your silver black, but I think that was discussing black silver on the outside, rather than recesses. I saw the link for the liquid, but has anyone tried it for recesses? Thanks again.

[josef1]

Maybe look at the low/temp enamels they can be sanded and polished

[china]

Or this https://www.jewellerssupplies.com.au/page/22/u-namel

I do not know who sells it in the UK or as I have recently discovered you could have Black Ruthenium plated or set yourself up to do it would not be practical for a one off, over time it will wear off
although being below the surface it would most likely take a fair amount of time.

Just o add if you have it plated you will have polish off the outside plating or there maybe some type of resist you can use

[Susie]

Ah, that's really interesting. I hadn't really thought of going down the enamel route. I will definitely investigate it.

[china]

Susie if you go the u-namel way experiment on some unimportant items first it can be a bit tricky but once you are au fait with it is a breeze
you can use it in cases that won't accept the heat needed for glass enamel ( it is basically the same as the dentist uses for no metallic fillings)