Acetone Questions.

I am still new to coin collecting and all the talk of Acetone baths has caught my attention. Will the Coin Grading companies still grade a coin that has had an acetone bath? Is there a thread here on CoinTalk that illustrates the complete instructions of doing this procedure completely and safely? If a Mint state coin has PVC damage or dirt will this procedure harm the coin or damage it's luster from the bath? Do you need to wear a respirator while using 100% Acetone and would the swirling a coin in the acetone cause any damage to a coin?

 

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Not true. I'd say about 200 or 300 of them.
And maybe more if you try other similar topics such as
Coin cleaning, cleaning coins, Acetone, cleaning materials and on and on and on.
Still always ask since at times so many new people have not seen nor may not even knoww how to search for topics.
Probably need some standard topics that remain in one header place.
Cleaning coins or Acetone would be really close to the top of that list.
And as you mentioned is there a COMPLETE INSTRUCTIONS somewhere. That is one thing I've noticed that there is always a little missing in each such post. Recently I heard someone asking what you use to put or remove coins from Acetone. Everyone says to just do it but seldom is it detailed as to exactly how. Might be a great topic for a book.

 

Only well-sealed, glass containers should be used with acetone. It should never be allowed to evaporate at all while the coin is soaking.

Before you start with acetone, you should follow the polarity ladder. This process is conservation, NOT cleaning.

1) deionized water
2) acetone
3) xylene

Sometimes reversing the process is also effective, but only after following in order.

 

You know Im really inclined to believe that this air dry thingie is key.
I bought some compressed air in a can at Best Buy, and tried quick drying with that, but on numerious occasions I ended up with water spotting on the mirror finish, like what you would see on your glasses when you don't buy the "New and Improved" Cascade for your dishwasher.
Id really follow his lead on that.

 

If your acetone is of excellent quality, there is no need to rinse with water as the final step. The final step should be a rinse (not soak) with acetone. It will instantly dry the surface and evaporate. I use this on ALL of my Airtite stored coins so there is ZERO trace of moisture on the surface. Water is one of the most harmful chemicals to any coin surface.

 

I have a newb question about acetone baths since I've never attempted. Does this acetone technique leave a coin unnaturally clean or shiny looking? Or does it just dissolve and remove surface dirt and contaminants without affecting the finish of the metal. I have a lot of old coins that are dirty and well worn. As much as I like shiny little objects, I would think a brilliantly shiny but well-worn old coin would look unnatural and detract from its appeal.

 

Thank you. I am glad someone finally agrees with me. I think people may be very surprised at how impure their "distilled" water really is.

 

In at least most instances, no one will ever be able to tell that anything has been done to the coin by the acetone. In theory, anyway, if you put one of two identical new uncirculated coins through an acetone cleaning, you should not be able to tell them apart when done.

 

I agree with Thad & RLM also on not rinsing with any kind of water nor forced drying after the acetone. I actually final rinse the coin straight from the acetone container ( I use a small beaker so I can hit the coin with little loss). Excess could drain into a first rinse container if one didn't want to waste.

Although some say metal could be affected, I have never seen it, nor expect from its chemistry myself, that acetone can affect the metal under normal conditions. However, I have been surprised and disappointed a few times when after the acetone had removed some organic material, that the area under it was much different color from the rest of the coin. Most were pre- 1934 coins and some people used various oils and waxes to cover defects, which you then removed. So yes, the use of acetone is not a "no - brainer" decision. Some thought must be put into the question of what might happen/ Except in the case of PVC activity, then I feel one must take the chance, otherwise if the coin looks great, leave it alone. If acetone affects toning, it was artificial to start with IMO.

Jim

 

What do you use to safely hold the coin while placing it in the acetone and removing it?
Also I am a bit of a phobic around harsh chemicals, should I do this outside and or wear a face mask? Thank You for all this information.

 

Your wife/mother has been using it on her fingers for decades. The most dangerous thing I know about it is it is very flammable. I should be used with good ventilation.

 

well ventilated is key here, you don't want to be huffing those fumes. You'll get all messed up.

 

Indeed my friend. Unless you have access to a laboratory grade purification system, there will be dissolved ions, bacteria and organic contaminants present in "store bought" distilled water. Now, it's certainly better than tap water, but definately not completely clean. On the flip side, most acetone is pretty high quality. Most of the acetone you buy at hardware stores in gallon cans is likely the same grade (or close) as to what we use in the laboratory.

 

Right on!

If someone damaged their coin using acetone, it was their fault.

I should point out that it is possible to have some hydrolysis and form corrosive acids in the presence of UV light and air. I also seem to recall a paper I read on the formation of peroxides with acetone....can't remember.

http://pubs.acs.org/doi/abs/10.1021/j150340a018

However, you'd have to over-expose the coin to do that and have the right conditions. I've heard of peoples claims to acetone damage, but I think most of time it's from using an improper grade of acetone.....not to mention improper usage in a gross sense. Justcarl ran his own experiments with acetone and light and he saw no damage....I'm sure he'll comment. :kewl:

 

Acetone is not a "harsh" chemical. Your body naturally produces it even! I do recommend you minimize your exposure, but a little on your skin or a little breathing is not "harsh". Google "acetone MSDS".

 

It is even worse than that. Most impurities in water are salts - the stuff that stays on coins and then reacts with coins. At least when I was using it, the most common impurity in acetone is water (pure water) and then other volatiles. That is the stuff that goes away and does not affect coins. So even if the acetone has 10 times the impurities, it may have 1/10 the affect on coins.

 

Could you expand on this for those of us who have no idea what a polarity ladder is.
So, step 4 would be acetone again, and then you're done? or what?

 

Whats the amount of time required for a good cleaning without damaging
The coin??

 

not sure how this works, i have a question, sorry !

I have a large penny and the date is 180?. Is there anything I can do to perhaps take off a fraction of the top layer to see what that last number is ? Or any other ideas ? It just indistinct...Sorry if this is in the wrong category, I just signed up...

Thanks...

Mark N
Mechanicville, NY