Polishing up slightly scuffed stone

I have a peridot that is a tiny bit scuffed (no deep scratches). I read some threads about polishing stones but they really got into the scientific weeds, and didn’t really help me. Anyway - would cerium oxide work? Is there something finer than that? Thanks, Sue

We have discussed this topic a lot lately. Do a search and see what you can come up with. If you can feel the spot with your fingernail, I doubt that cerium oxide is the solution until you figure out how to grind/sand the damaged area down first. This may require that you remove the stone first…Rob

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Hi Sue,
Is it a faceted peridot or a cabochon? If it’s faceted, you’ll round out or completely destroy the facets. As Rob said, there’s info about shining up a mildly scratched stone in the forum.

But in answer to your question cerium oxide will work. But remember even with a cabochon, it’s going to be hard to not put a dent in the stone with polishing while the stone is mounted in a setting.

If it’s a stone where there’s no easy solution and you just want to make it look a little better, Zam and a buffing wheel will make your peridot be shinier. But again, you can just do a little bit of polishing as you’ll round out facets with that technique. (But sometimes in a repair and the customer’s approval, that’s better than not doing anything.)

Otto Frei recently highlighted this fine diamond flex shaft/micro motor wheel for polishing out light scratches. I’ve never tried it, so I’m not recommending it, but it’s a product that is designed to do what you’re asking.

Really the answer depends on what your goal is? If you’re doing a repair on an older piece of jewelry and trying to make the jewelry object look better, that’s one scenario. If you’re trying to make it look brand new after being scratched, that’s a lot harder to do with the stone mounted in a setting.

Hope that helps!

Jeff

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Oh, I forgot to say. Rob is correct! If the scratch is deep enough to catch in your fingernail, cerium oxide won’t remove it. It will make the stone shinier though. Jeff

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It’s not a scratch, it’s just a light scuff, as if one used, say, 3000 grit sandpaper on it.

That looks excellent, but I will hold off until I have more to order, since the cheapest shipping to Canada for that is $47. Crazy. I get large and fairly heavy boxes from Rio for about $35.

My first and last job (I didn’t like the nerves of fooling with someone else’s stone) as a faceted stone repairperson was an amethyst with a scratched table which a jeweler had tried to fix with a Foredom. You can’t get a flat facet with a little round wheel…there are a number of “gem doctors” who will fix such for you for under $100 if it is just slightly scuffed, as all that is required is a light repolish of the table. If you have to undertake this yourself, I would recommend that you use a piece of flat acrylic plastic. Mix up a little cerium oxide and water, apply it to the plastic “lap” and hand hold the stone and ring flat to the lap while moving it round and round. If you are careful, you won’t round the facets much and the polish will come back if the scuff really is just 3000 grit sized scratches. If you are lucky, polishing won’t take off much of the star facets and the facet meets will remain about as they should be. If polishing takes too long, you are left with star facets that don’t look exactly right and then you may be back to sending the stone off to be fixed, which it surely can be…the original Gem Doctor is Anthony Lloyd-Rees, and he is a good one and could advise you further if needed. Just google him.
-royjohn

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Thank you, I will try that. It’s a peridot and not expensive - if I can’t do it I’ll just replace it with another one.

Update: I did get the Agilo knife edge extra fine cabshine a while back, and just used it for the first time on a rosecut rhodolite I accidentally scuffed with a file - it works really well! I’m so happy I’ve finally got something for when this kind of thing happens.

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