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Ted Mooney, P.E. RET
The authoritative public forum
for Metal Finishing 1989-2025
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How to get dark black surface in Turkish men's rings
Q. Hi. Need to achieve dark matte black finish on my Turkish gents rings. Please advise how ? Also, liver of sulphur is available but anything apart from that is not. So please advise me accordingly.
Ankit kohluOwner - Gurugram, Delhi, India
March 20, 2025
A. Hi Ankit.
Are these rings a couple of your personal possessions or are you a supplier of them?
Presumably your rings are sterling silver, but if they are bare sterling silver they will tarnish easily. Do they tarnish?
If they don't tarnish they are rhodium plated or have a clearcoat of some sort. And while liver of sulphur is a good darkening agent for silver, if it can't get to the silver due to rhodium plating or a clearcoat, it can't blacken it.
If you are a supplier, rather than talking about a couple of your own personal rings, black rhodium plating or black ruthenium plating may be preferable to a black sulfide ... but we have the same question of whether there is a plating or clearcoat presently on the rings or not ... and tarnish would be the easiest indication that there isn't.
Luck & Regards,
Ted Mooney, P.E. RET
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
Q. Hi, I am starting up in jewellery manufacturing and dealing in sterling silver. We made rings in sterling silver without any rhodium coating. By using liver of sulfur we are able to get dark "gun metal" look but it's not dark black.
My concern with using ruthenium or black rhodium is that if use it we won't a solid finish which liver of sulfur after drying gives, but a very liquid look -- that concerns me. Can we use black nano coating for matte look?
Owner - Gurugram, Delhi, India
March 22, 2025
A. Hi again. Yes, it would seem that liver of sulfur will give you only the look of badly tarnished silver, not a true black. Are you trying to to make rings that are all black, or to blacken just the recesses, with the outside surfaces polished back to bright silver? -- such as we see in high school rings ⇨
They are different problems since the blackening in the recesses experiences very little wear, so you have many options including the new super black paints, or mixing india ink into epoxy, black e-coating, etc. If the whole ring must be black, you would need a rather thick highly wear-resistant coating.
Luck & Regards,
Ted Mooney, P.E. RET
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
Q. Hi again , yes exactly as this ring we need. High polish area with dark black . When you mention paint, it gives shiny surface and not matte black and also it gives wet look and not thin layer look ... also we are not able to get even surface but wavy. When you mention epoxy what kind of epoxy we looking at? Thanks in advance
Ankit Kohli- Gurgaon
March 23, 2025
A. When an object or coating is sufficiently black, the concept of matte vs. shiny no longer has meaning 🙂
There are several routes to super-black coatings. "Vantablack" is one, but being based on carbon nanotubes it doesn't sound applicable to your needs. Super-blacks by electroless or electrolytic deposition of nickel-phosphorous, followed by etching in nitric acid or anodization in non-oxidizing acids, seems exactly right for your application but I don't know if it is commercially available as a fully developed process or whether you would need to do development work (you can google "NPL super black", or do scholar.google.com with some applicable terms to start tracking down what the state of the art is).
I am not a jeweler but found many suggestions like the epoxy with india ink quickly by googling.
Still, if you don't want new generation very black paints, nor the substantial development work for super black nickel phosphorous, I think there are commercially available blackeners that most jewelry manufacturers find sufficient like "Silver Black" from Santa Fe, Rio Grande, Grobet, or Griffith. You can google for a "safety data sheet" and learn the essentials like that they [at least some of them] contain strong HCL with a little tellurium IV oxide.
Thread 218/68, "How to oxidize silver (wire, chain, jewelry clasps)?" offers additional discussion on these commercial silver blackeners.
Best of luck,
Ted Mooney, P.E. RET
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
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