Can I restore this decorative stone bowl?

January 30, 2018 5:17 AM

My wife and I were given a nice stone bowl as a wedding gift about 10 years ago. Over time, it's gotten some discoloration and "tarnishing." I'm not sure what type of stone it is, or how to clean/polish(?)/seal(?) it. How would I go about this?

Here are two pictures showing details of the bowl and parts where it's... worn? Washing it cleans it, but doesn't do anything to remove or change the damaged bits, which seem more like lost finish and erosion than anything that's built up on the surface.

posted by Shepherd to Home & Garden (7 answers total)

I'm guessing it's a sealer that has gone bad in spots. You could try to remove it with lacquer thinner (well ventilated area, like outdoors with a fan blowing it away from you, or using a respirator made for solvents (home depot)). Try a small area first. If that works, remove all of it, then seal it with a granite counter sealer.
posted by H21 at 5:48 AM on January 30, 2018

If the stone is marble or some other carbonate then these marks will be etching stains caused by acids from fruit or other sources. You can buy etch remover, which is an abrasive that polishes away the surface layer where the stone has reacted with the acid.

Assuming the above is correct, you'd need to add a protective coat to the stone to prevent the reaction recurring, or just not put anything acidic into it in future.
posted by pipeski at 6:22 AM on January 30, 2018

I would also guess that those spots were caused by something acidic like fruit juice or tomato juice.

You might contact a stone finisher in your area - someone who installs marble, granite, etc and ask them what product they would use and/or if refinishing a small project is a service that they provide.
posted by vignettist at 7:32 AM on January 30, 2018

Hi there! I am also co-owner of said bowl, we do use it to primarily hold fruit, so I'm guessing that you all are right and that is what is eating through the finish.
posted by Kitteh at 7:51 AM on January 30, 2018

Try using plain tooth paste with 0000 steel wool .
posted by hortense at 8:56 AM on January 30, 2018

If you put a dab of water on the stains do they get darker? If you put a dab of mineral oil (or canola or whatever you have on hand) on the stains do they get darker?
posted by gregr at 10:07 AM on January 30, 2018

If it were me I would just buy some 400 grit wet/dry sandpaper, sand the whole bowl down, and then put a thin layer of food grade beeswax on it and rub the wax in.
posted by gregr at 10:10 AM on January 30, 2018