Black Junk on Silver...

SugarSand · May 6, 2005

I found my 1st and only silver dollar 5 years ago.? Unfortunately, it has some evil black junk stuck on the front.? It's raised like a hard tar or something, and isn't the lovely toning I see on some old silver.? The back is also very dull and dingy unlike any other silver I have found.? I'd appreciate any ideas on how to help it out.? The usual baking soda rub did nothing to help.? I'll try something mild but nothing drastic because it's a nice conversation piece the way it is.

jimmyokla · May 6, 2005

WD-40 will melt tar or any sticky tar or oil substance and i doubt if it would hurt the coin since its metal .......works good for road tar on your car too lol

SugarSand · May 7, 2005

I agree that WD-40 dissolves tar and the like. I also have a mineral spirit based product called TecNu that removes poison ivy oils and does a great job on things like that too. After sitting with WD-40 on it for 2 hours the black junk remained rock solid though. I'd have to guess some kind of plant life laid in the ground touching it when it was lost and this is the "coal" that's developed over the past 70 years it was laying there. I think I'll try what Badger suggests, now all I need is an aluminum pan and non-iodized salt...

Thanks

buckeyehunter · May 7, 2005

ok, maybe this is a bad suggestion because I dont know a lot about coin cleaning but my brother found a 1964 quarter a few months close to a black top driveway while we were out detecting, tried SEVERAl different methods of cleaning it with absolutely nothing working.... a friend of his a few weeks ago recommended using tooth paste and a gentle toothbrush... after a few minuites it was completly clean and looked like a brand new one! we were shocked how beutiful and new it looked considering everything else we had tried but like I said..... dont know much and this might be an awful way to clean one ( we dont clean our silver but this one was so bad... nothing to lose) but would love to hear if anyone else ever uses toothpaste?

buckeyehunter · May 7, 2005

michigan badger, I will deffinently keep that in mind, sounds like it works great!

Mike

SugarSand · Jun 13, 2005

Hey Badger, I haven't had a chance to try the cleaning yet. Too busy with other things now, but I will try it sometime. I tried twice to reply to your PM but your Inbox is FULL.

PrizmIV · Jun 21, 2005

Try the citrus de-solv-it it works increadable!

MUD(S.W.A.T) · Jul 27, 2005

Please show us an after picture!!

HH!!

mattjd · Aug 12, 2005

You can also try lighter fluid. But if that doesn't work just buy a dollar from a coin shop that has the same date and is in the same condition as that one just without the black on it. LOL!

Nice looking detail on that one.

Matt

SugarSand · Sep 11, 2005

Thanks for the idea, Conservator. It's been soaking in 70% for two full days now in a sealed baby food jar, and I just tried the Q-tip. Only one really tiny black flake came off, nothing else. I'll just let it sit in there for a few more days and try again unless you suggest something else. That black stuff reminds me of some permanent aviation gasket sealer I saw once 20 years ago...

bk · Sep 12, 2005

The black crud looks to me like silver sulfide. Did you find the coin under a cement sidewalk?
If the material is tar or some similar petroleum compound, try soaking it in acetone, but be careful, acetone is highly flammable.

PrizmIV · Sep 12, 2005

bk said:
but be careful, acetone is highly flammable.

LMAO!!!! I have started a few "controlled" fires with that stuff ::)

SugarSand · Sep 13, 2005

The iso alcohol is the only extended soak I've ever tried. I did try the WD-40, Tecnu, and Ethyl alcohol with a Q-tip but nothing can phase this stuff. Wonder if acetone or gasoline will hurt the silver?

weldermark · Sep 13, 2005

just a suggestion but what if you froze it and tried to scrape the junk off with your finger nail or a piece of soft wood

HH Mark

Vrent · Sep 16, 2005

besides using a q tip try using a toothpick, or piece of balsa wood, to worry the crust if you can't remove it it is ok, just try to get some openings in it so the iso can soak in

no toothpaste, abrasive

Luck Vrent

SugarSand · Sep 16, 2005

Thanks everyone! I have come to the conclusion that this really is silver oxide (sulfide?) and it wont be removed without some form of electrolysis or mechanical means. I think whatever was against it has corroded the silver itself and this is the way it is. It was found in the backyard of where a house used to be, circa 1910. I still like it and will just probably leave it this way as one of my cool finds. Thanks for all the ideas and help!

Gigisdiamonds · Sep 17, 2005

Hi ...how about trying a woman view lol $:-\$ The dollar store has something called Gojo it will remover tar. My brother works with a road crew and this works on his clothes . Just let it sit on it as long has it takes and rub in and work off slowly if you have to. It won't harm the coin and it is cheap to try. Give it one more try and you will be very please I'm sure!

Good luck! H.H
Gigi

Matejko · Sep 17, 2005

Hi SugarSand !!!

Have you tried this.:

Get a plastic or glass container, fill it with warm water (250-300ml) put 2-3 large spoons of salt into the water. Mix it properly.
Then, at the bottom of container place some aluminium foil and put your coin on the foil for a few hours.

Sounds strange, but works. I assure.
Here is a picture, how should it look like.

Pozdrawiam Matejko

SugarSand · Sep 17, 2005

Thanks Matejko! I have seen a similar method before from Comanchero but never tried it because I didn't seem to have the right salt or aluminum on hand at the same time. I went ahead and tried it today with some iodized table salt and a piece of aluminum sheet metal I had in the garage. The black junk is definitely silver sulfide because I could smell the hydrogen sulfide (rotten egg smell) coming up from the container. The black junk immediately started flaking off, but the reaction seemed to stop after 30 minutes with my current salt solution. I did it twice for 30 minutes each time and here is a picture of the results. The raised black is gone but the affected area is still not clean by any means. The coin is also shinier. I'm going to try and get plain salt tomorrow and retry.