Do fingerprints affect a proofs grade

what about so called 'coin tongs' ?

 

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Thanks Krispy...I had never heard of them honestly !

 

Sorry to hear about your coins
Not sure how to get rid of those prints but NGC has a "Conservation" service but I dont if that would work for your coins
You say these were PF 65's ? To me these are so expensive coins I would never buy or
put them all together in a roll they would get all nicked up and not be 65's any more .If I got these I would haved checkd each and everyone of them with gloves and a loop .
http://cgi.ebay.com/1951-Proof-Half-50-PCGS-PR65-White-Blazer-/380248075216?pt=Coins_US_Individual

 

@ kangayou: They are basically laboratory supply items. I bought the cheapo blue plastic Kointongs and found them useless, especially for anything larger than a US quarter. Perhaps something stainless steel with cushioned tips (that won't dissolve in chemicals) would be the best investment if using these.

 

Thanks Doug. I may do an experiment on the golden dollar since I feel the coin is too far gone with prints having been on there for an undetermined amount of time. Can't really hurt this one much more. I suppose I would first approach with a, very brief, Acetone bath. If no results from Acetone, then move to MS-70, again briefly. I've got the before pics. Will post after pics whenever I get done doing this experiment.

 

Duly noted! :thumb:

 

but that gives us something else to learn from this! We get before pics, after pics, and way after pics.

 

give us exact pics for the coins before and after for coin 2 not different angles. also throw in a pic lets say 3 months after that will settle most doubts

 

UPDATE:

I've followed through with an experiment to test the results of removing fingerprints from this coin in an Acetone bath.

Using fresh, pure Acetone, I laid out three glass bowls with just enough Acetone to cover the coin. The coin was placed in the first dish for a period of 15 minutes and rotated (flipped over) every five minutes. Then it was moved to the second and third bowls, continually rotated at each five minute interval. Lastly the coin was rinsed in a dish of distilled water and allowed to air dry propped up in an upright position over a soft cloth.

The image below compares the before and after results, of which very little removal of prints can be noted. No attempt was made to swab or massage the coin while immersed in Acetone. To repeat, this Proof coin was found in circulation and was covered in prints that had been there for an indeterminable amount of time.




As this 2007-S Proof coin is 'damaged' with fingerprints and has now been placed in an Acetone bath I will decide if I would like to test MS70 Coin Brightener on it or not. My experience with MS70 is limited but I have found that it removes a significant amount of dirt and surface contamination (having tested on junk silver) when worked VERY gently with a cotton swab. It is easy to over apply MS70 and it is a rather viscous (binding) substance which requires plenty of rinsing in distilled water to remove. Silver can come out overly shiny by over extending the time cleaning in MS70 and clad coins do not seem to react well to MS70 leaving them dull. I have never cleaned a Proof coin with MS70 but performed the following test on these two 'golden dollars':

2008-P Martin Van Buren $1 with fingerprint, lightly circulated & 2000-P Sac $1 well circulated with dirty spots around inside of rims.


BEFORE applying MS-70 Coin Brightener





AFTER applying MS-70 Coin Brightener




Notice that the Martin Van Buren coin has a rather noticeable fingerprint on the obverse over the portrait. Cotton swabs were used gently with a liberal application of MS70 for approximately five minutes on each coin. This removed the print and returned the lightly circulated Van Buren coin to a near flashy condition, but the Sac was not rendered so flashy, having started out more toned and worn from longer exposure in circulation. The spots around the edges (rims) of the Sac coin left noticeable exposed areas that are lighter and ring stained by the dirt or corrosion that was there before.

Following my experiment with the 2007-S Proof GW Presidential golden dollar coin (above), since I had the Acetone and dishes ready for use, I soaked the following two Sac $1 coins in Acetone. Again, I sent the coins through the three stages of Acetone in separate glass dishes, rotating each coin after 5 minutes for a total of 45 minutes in Acetone followed by a rinse in distilled water and allowing the coins to air dry in an upright position. I found very little effect from the Acetone and, in-hand, perhaps the slightest intensifying of 'red' tones in some regions of the Sac coins, particularly on the reverse. The Sac coin on the left side had several dark spots on it which were removed or rendered lighter and now appear whitish in place of the dark ones.

I apologize that my camera equipment is not sophisticated enough to show all of these details, but hope this provides a general visual record of my experiments cleaning Sac and Pres dollar coins.

SACs BEFORE Acetone bath: 0 minutes





SACs AFTER Acetone bath: 45 minutes




Finally, all of these coins have been placed in pvc-free flips and labeled for their cleaning and dates of treatment. In the event that three months or so down the line they have made any significant changes I will try to report back.

 

Thank you for taking the time to do this Krispy ! I am interested in the longer term effects.
That Martin Van coin came out amazingly !

 

I'd say you are going to be correct!

Fingerprints sure are pesky things. ...and what the image I posted can't show well enough is remaining evidence on the MVB pres dollar that the print was not fully removed. Further examination shows that a partial print was left over in the field at 4 o'clock on the obverse as well as on his jacket lapel between 4-5 o'clock positions. [Again, this was one of the coins that MS70 coin brightener was applied with a cotton swab.]

 

I understand what you are saying about the print being etched into the metal. I'm curious about the degree of this, not to suggest that I am hopeful in any way to reverse that which cannot be reversed due to the amount of time the print was allowed to set in and the metal around the print to change, but curious if it is more the oils in the print, that may contain acidic qualities, which are more responsible for the 'etch' or if a fingerprints greasy quality actually acts to protect the metal it covers and what appears as an etched print is due to changes of the exposed metal outside and around the print itself? I suppose it can be a near impossible combination of the these factors from one print-laden coin to the next to cite the exact cause, especially when we don't always know before and after conditions in which the coin obtained the print let alone the unique qualities of the print-maker. The very nature of one person's print differs from another person's as our chemical make up, skin cells left behind or the prescience of foreign matter on fingertips at the time of leaving a print on the coin all vary. Inability to determine those factors precisely may suggest that 'time' is our ultimate factor of gauging successful removal of a print from a coin. If time is not to our advantage the degree of the other factors works against successful removal of a prints effects on the coin. The time the print has been allowed to set in (etch) and change the metal, or the metal around the print to further oxidize in the environment it is stored or traveling around in, simply cannot be reversed. What's done is done.

I have also done a few experiments with MS70 on copper LMCs, on pre-82 and those that came after, and I know that it makes for some wild AT! Deep blues and magentas are easily obtained.

 

yet we are so happy to give them our $20

 

I have noticed this on both pre and post 1982 LMC's when using dirty acetone. I experimented with some common circulated cents sarting with dirty acetone and then rinsing with tap water and drying with a towel ( all intentional no-no's ). They started to obtain those purple & blue tones sort of like the oils you see in the run off water in gutters shortly after rain begins to come down. Then I rubbed "Pantene Pro-V Brunette Expressions Daily Color Enhancing Shampoo" liberally and evenly over the whole coin and rinse with tap water withing 20 seconds (any longer it will bleach the coin to off-white) and once again dried roughly with a towel and now I had purples , blue, yellows and brown tones that moved in a rainbow tone as I swirled/tipped the coins. Something I haven't done is to check the status of those same coins to see what the long term effects would be.

 

If you have any images of your experiments, I would enjoy seeing them, be they recent or long term effects.