My sons Sterling Rosary is looking much older than it actually is! |
Here's what I did....
First I gathered together the following:
Aluminum foil
2 teaspoons Baking Soda,
1 teaspoon Salt,
Warm water
a bowl
a tarnished silver rosary
I lined the bowl with enough Aluminum foil that would easily cover the bowl without water getting out.
I poured hot water into the aluminum lined bowl....
Added the Baking soda and salt and mixed....then threw in the tarnished rosary in the warm water and watched.
NOTE: Make sure the tarnished silver parts come in contact with the aluminum foil....this is a must!
Can you see the little flakes rising to the surface? It looks like snow. |
Right away I could smell an odor not too different than liver of sulfur. I did the experiment outside, because I didn't know if the gases would be toxic.
I stirred my rosary around...to get all the parts in contact with the foil.
I saw white flecks floating in the water...I wondered if that is oxidized powder that is floating off?
My water was quite hot...but not so hot to burn me. I wondered what temperature was the best? Wood boiling water be better?
Every now and then I swirled the rosary around and checked on it. I didn't want it to be a bright silver...but I wanted it to retain just a little of the aged look.
After I was finished, I dried the rosary parts off with a soft cloth.
A little of the oxidization rubbed onto the napkin that I was using. The pieces looked pretty good again.
Here is the finished rosary. The medals have lost the deep dark grey and have retained a vintage look...without being overly shiny. I could probably have left it in the water longer, if I wanted a shinier look.
When I gave the rosary back to my son, I told him that when he prays the rosary, the oils from his hands will help prevent oxidation...and when he's not praying, it should be in a rosary pouch. I handed him an anti-tarnish rosary pouch...and hopefully, I am not going to have to shine it up again!
I had so much fun, I decided to try the experiment with some other silver pieces. The ladle and the candy dish below were pretty tarnished. This time I used boiling water, and left them in the water for only a short time.
I didn't know if the pieces were real silver or silver plate...but I forged ahead anyway....
The candy dish started brightening right before my eyes. But it occurred to me that it was most certainly silver plate....so I took it out pretty quickly since I wasn't sure if this would destroy the thin layer of silver. The candy dish is still a bit mottled...but still looks much better than it did before!
I would guess the ladle is also silver plate. But it looks way better too.
(After reading the science behind this experiment, it appears that this process should not be harmful to silver plate...unlike commercially available tarnish remover)
So what actually happened in this experiment? I looked up the science of it after I was done, and this is what I found.
When silver tarnishes, it combines with sulfur and forms silver sulfide. Silver sulfide
is black. When a thin coating of silver sulfide forms on the surface of silver, it darkens
the silver. The silver can be returned to its former luster by removing the silver sulfide
coating from the surface.
There are two ways to remove the coating of silver sulfide. One way is to remove the
silver sulfide from the surface. The other is to reverse the chemical reaction and turn
silver sulfide back into silver. In the first method, some silver is removed in the
process of polishing. In the second, the silver remains in place. Polishes that contain an
abrasive shine the silver by rubbing off the silver sulfide and some of the silver along
with it. Another kind of tarnish remover dissolves the silver sulfide in a liquid. These
polishes are used by dipping the silver into the liquid, or by rubbing the liquid on
with a cloth and washing it off. These polishes also remove some of the silver.
The tarnish-removal method used in this experiment uses a chemical reaction to convert
the silver sulfide back into silver. Many metals
in addition to silver form compounds with sulfur. Some of them have a greater affinity
for sulfur than silver does. Aluminum is such a metal. In this experiment, the silver sulfide
reacts with aluminum. In the reaction, sulfur atoms are transferred from silver to aluminum,
freeing the silver metal and forming aluminum sulfide. Chemists represent this reaction
with a chemical equation.v
3 Ag2S | + | 2 Al | 6 Ag | + | Al2S3 | |
silver sulfide |
aluminum | silver | aluminum sulfide |
The reaction between silver sulfide and aluminum takes place when the two are in
contact while they are immersed in a baking soda solution. The reaction is faster when the
solution is warm. The solution carries the sulfur from the silver to the aluminum.
The aluminum sulfide may adhere to the aluminum foil, or it may form tiny, pale yellow
flakes in the bottom of the pan. The silver and aluminum must be in contact with each other,
because a small electric current flows between them during the reaction. This type of
reaction, which involves an electric current, is called an electrochemical reaction.
Reactions of this type are used in batteries to produce electricity. (This information was taken from the following website http://scifun.chem.wisc.edu/homeexpts/TARNISH.html)
How coool is that! (I have always loved science!) Now I know the little flakes I was seeing was actually the aluminum sulfide. I also read (you can read the whole article at the link) that it was better to use boiling water in the experiment. That is good to know for future reference.
It is also worth noting that the gas that I smelled must be Sulphur Dioxide which is produced when the Sulphur combines with Oxygen. This is a toxic gas and is best avoided with plenty of ventilation.
I think this experiment is a huge success, and I know this method will come in handy in the future for other tarnished silver pieces. It is so easy...you should give it a try!