From all that I've heard Acetone does not chemically react with the silver (or Gold) coin metal, but is used to dissolve certain types of chemical impurities which have attached themselves to the coin, such as PVC from the old soft plastic clear coin flips made with PVC.
Stuart
Collect 18th & 19th Century US Type Coins, Silver Dollars, $20 Gold Double Eagles and World Crowns & Talers with High Eye Appeal
"Luck is what happens when Preparation meets Opportunity"
I have found that it is good to rinse the coin with distilled water after the acetone dip. Since any acetone you buy won't be 100% pure, it can leave a white deposit on the coin. At least the acetone I have used (which is listed as 99.99% pure) has had this effect.
Thank You Guys....I am armed with Acetone in hand and a gallon of distilled water....I am going to complete this mission...now to find the glass containers.....
Anyone who says you should bring baking soda within 10 feet of your precious coins should be locked up and smacked with a trout. Baking soda will eat holes in silver and copper coins and is very difficult to disolve, leaving particles of soda floating around in solution. Pure Acetone does NOT leave a residue and is an appropriate final step before putting a coin into a new holder.
I prefer Isopropyl alcohol myself (95% or better) because I don't risk blowing up my house.
"...reality has a well-known liberal bias." -- Stephen Colbert
One more thing I forgot to mention. Acetone evaporates so quickly that is has the property of taking a lot of heat away from the coin and making it very cold. The residue that people talk about is probably condensation from the cold after the acetone evaporates. This water comes from the air and should be nearly pure, so let it dry or blowdry it before putting it away.
"...reality has a well-known liberal bias." -- Stephen Colbert
I've used acetone on proofs that have residue from plastic. I used a couple of 'baths' to keep the dissolved impurities from recoating the surface upon drying. The sequencial baths of fresh acetone uses a serial dilution technique to get rid of the plastic stuff.
However, I perceived that the acetone still leaves some traces so I've tried drying with isopropanol. Hitting the coin with heat from a hair dryer is good since it doesn't contact the coin, but getting the coin too hot can be a problem. (You drop it!)
I'm still experimenting. If the coin looks pretty good, I leave it alone.
All these solvents are flammable and not good to breathe. Use lots of ventilation and keep away from sparks and heat sources. (Don't heat the coin with the dryer then put in the acetone. You'd be asking for a Richard Pryor.)
Collector of Modern Silver Proofs 1950-1964 -- PCGS Registry as Elite Cameo
That's what I had to do...multiple rinses with isopropanol.
Couple of dumb questions. I've seen that acetone residue after removing a proof coin from an acetone dip -- looks like little oil spots covering the surface of the coin. And you can even see it on business strikes if you look close enough. I've posted a closeup from a modern Kennedy MS coin below -- several forum members have warned that retail acetone simply is not good enough because of impurities, and thus people should, at a minimum, undertake an additional rinse in distilled water.
First, is "isopropanol" the same thing as "isopropyl rubbing alcohol 91%," i.e. the opaque plastic bottles you buy at the drug store?
Second, you've found no adverse effects when going from acetone to isopropanol?
Finally, the isopropanol leaves no residue -- or are you going to a distilled water bath as the final step?
Why don't you with acetone questions just do a search?? It's been discussed and rehashed so many times! >>
You're just PO'd that your Franklin is not FBL
Yes, isopropanol is rubbing or isopropyl alcohol. I use the 91% stuff, and after several rinses I just pat it dry very carefully. It's worked fine so far. I guess a distilled water rinse couldn't hurt.
dlimb2
Posts: 3,449
Comments
Stuart
Collect 18th & 19th Century US Type Coins, Silver Dollars, $20 Gold Double Eagles and World Crowns & Talers with High Eye Appeal
"Luck is what happens when Preparation meets Opportunity"
the removal of the chemical from the coins surface. These are well know - respected people whose
anonimity I will honor.
One advocates soaking the "cleansed by acceptable means" coins In a bowl of hot soapy water
after the "enhancement" procedure.
Another says that he likes the fewest agents as possible to come into contact with the surfaces while
still another recommends one tablespoon of baking soda to a cup of water to remove chemicals.
The common key is to get the chemical, whether it is MS 70, ez-zest or Acetone, completely
off the coin then to rinse THOROUGHLY in warm water for a full minute or so and last but not least, to
either pat the coin dry or to use a hair dryer. From what I understand, Acetone evaporates!
PATTING, however, involves yet another thing coming into contact with the surface of the coin.
Myself, I have yet to try any of these methods as I am from the school of "don't mess with it"...
...however, obviously there are times that common sense would dictate that a good bath can
greatly enhance a coin's eye appeal! Hope this helps.
I prefer Isopropyl alcohol myself (95% or better) because I don't risk blowing up my house.
Jim
I'm not sure myself. I know what will work. Your thoughts?
However, I perceived that the acetone still leaves some traces so I've tried drying with isopropanol. Hitting the coin with heat from a hair dryer is good since it doesn't contact the coin, but getting the coin too hot can be a problem. (You drop it!)
I'm still experimenting. If the coin looks pretty good, I leave it alone.
All these solvents are flammable and not good to breathe. Use lots of ventilation and keep away from sparks and heat sources. (Don't heat the coin with the dryer then put in the acetone. You'd be asking for a Richard Pryor.)
Link to 1950 - 1964 Proof Registry Set
1938 - 1964 Proof Jeffersons w/ Varieties
That's what I had to do...multiple rinses with isopropanol.
Couple of dumb questions. I've seen that acetone residue after removing a proof coin from an acetone dip -- looks like little oil spots covering the surface of the coin. And you can even see it on business strikes if you look close enough. I've posted a closeup from a modern Kennedy MS coin below -- several forum members have warned that retail acetone simply is not good enough because of impurities, and thus people should, at a minimum, undertake an additional rinse in distilled water.
First, is "isopropanol" the same thing as "isopropyl rubbing alcohol 91%," i.e. the opaque plastic bottles you buy at the drug store?
Second, you've found no adverse effects when going from acetone to isopropanol?
Finally, the isopropanol leaves no residue -- or are you going to a distilled water bath as the final step?
Why don't you with acetone questions just do a search?? It's been discussed and rehashed so many times!
and they're cold.
I don't want nobody to shoot me in the foxhole."
Mary
Best Franklin Website
<< <i>Ohhh god...not another acetone thread.
Why don't you with acetone questions just do a search?? It's been discussed and rehashed so many times! >>
You're just PO'd that your Franklin is not FBL
Yes, isopropanol is rubbing or isopropyl alcohol. I use the 91% stuff, and after several rinses I just pat it dry very carefully. It's worked fine so far. I guess a distilled water rinse couldn't hurt.