Help save my 1934 Texas Centennial Half Dollar...!

Then most likely you caught it in time , though it may have affected the luster . I'd love to see a pic when you're done , sort of like a before and after pic . Good luck .

 

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Remember the ALAMO!!!

 

Several posts on different threads suggest that "rinsing" is not helpful in dealing with residue PVC. IMO, I would use 2 to 3 different cups of hi quality Acetone to deal with the residue; should also help with any other "gunk" on the coin

 

Acetone (Certified ACS), Fisher Chemical

Meet or exceeds the latest ACS specifications. Actual lot of analysis on label



Chemical Identifiers
Chemical Name or Material Acetone
CAS [67-64-1]
Purity Grade Certified ACS Reagent Grade
Physical Form clear liquid
Assay 99.5% min.
Molecular Formula C3H6O
Formula Weight 58.08
MFCD Number MFCD00008765
UN Number 1090
Merck Index 15, 65

This is what i will use for the soak.

I'm thinking of doing a complete log of the process.
Volume,time,temp,etc..!

I also could boil the acetone..!?
maybe that would do a better job, maybe not..?

Thanks

 

Right now I am using a glass pickle jar to soak a 1938-D Half that got returned from NGC. My wife washed the glass jar out several times with liq. soap, then in the dishwasher 3 times to sort of sterilize it. I think I will leave it in the jar with the lid sealed for a week or two.

https://www.cointalk.com/threads/how-log-should-i-soak-this-in-acetone-for-pvc-damage.265844/


I would NOT advise on boiling the acetone

 

No worries..!
It's perfectly normal, we have a bank of hot plates boiling acetone,etc. 24/7, it's all in a closed system...

 

But you do not want to artificial tone that coin from heat !

 

Thank's,
was not aware of that at all...!

Just some cold acetone it is..!

 

Do two or three baths of acetone for an hour or so each and see what you have.
No rubbing of any kind.

 

Well I have began the process as I type this the coin has been soaking for about 30 minutes. I will let it soak for about 1 hour, then see if there has been any changes.
I also picked up a little DI water to rinse it with may be at the end. Also have a can of compressed air to make so I can quick dry it.

The acetone should flash off with out a trace pretty dang fast, might not use the water. Just rinse with clean acetone at the end.

 

Still better to rinse with water. Even though it evaporates it'll leave stuff behind that could still damage the coin. And I'd avoid the compressed air as well. Just let it air dry.

 

Rinsing with water is OK to make sure all the contaminants dissolved in the acetone are gone, but a final rinse with fresh acetone will remove the water and dry the coin in a flash. No risk of waterspotting from air drying or hairlining if you "pat" dry.

 

OP....If you are going to dip it more, it would be interesting to see after pictures. Let us know how long you soaked it for. If you have time, and willing

 

Well I had to leave unexpectedly for the weekend. So I wasn't able to monitor the progress completely. I ended up leaving it soaking almost continuous for 48hrs.
At first I was checking it every few hours, and nothing was changing, so I put it in fresh acetone Saturday morning and just got home, and I definitely can see a difference in the coin, it looks like all the PVC is gone, and just the black spot remains. The front looks brighter and, the back looks the same.
I'm trying to do a better job with the pics, I'm using my rebel t3-I, with the smallest lens and macro setting, Ios is 200, if anyone has some suggestion's to help.
It just started pouring rain here, if the weather breaks and I can get some sunlight I will try to get pics today, but if not I will first chance I have..

I would say it was a success..!
The coin looks a 1000 times better..!, doesn't look like it was tampered with at all.
No unusual bright, really clean spots that look like they don't belong there...

 

So where's the picture already?

 

Acetone at normal pressure boils at 56C, 133F. Pretty sure that's nowhere near hot enough to cause quick toning, particularly with oxygen excluded. (If you don't exclude oxygen, the boiling acetone will displace it very quickly anyhow -- assuming you don't get an explosion or fire first.)

 

Piggybacking on this theme,
will getting the crud/pvc off the coin effect it's value?
Would one say that the coin was cleaned up with acetone??
Not positive, but "feel" it's accepted practice, and would note its acetone bath if listed on Ebay.

 

This answers the question I was getting ready to ask, thanks! I've always stuck to the "never clean a coin unless you're an expert" mentality, just because I didn't want to ruin something. But, it seems acetone and silver = ok. Anything else to consider?

 

AND WHERE ARE THE PICS?!?!?