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 Replies: 10 / Views: 2,118 |
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New Member
United States
21 Posts |
Hi, I have plenty of coins with rubbed off dates specifically Standing Liberty quarters and some Mercury dimes. What are your methods of retrieving them ?  Most preferably, is there any way to reveal the dates without inflicting damage to the coins ( at least not much damage ). How does the PCGS do it ? I have seen a few coin listed as a 1916-D Mercury dime with a rubbed off date. Let me know ! *** Moved by Staff moved to a more appropriate forum. *** |
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Bedrock of the Community
 United States
12477 Posts |
In Memory of Crazyb0 12-26-1951 to 7-27-2020
In Memory of Tootallious 3-31-1964 to 4-15-2020
In Memory of T-BOP 10-12-1949 to 1-19-2024
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Moderator
 United States
14463 Posts |
I moved this topic to the Classic Coin Section. Since the majority of ND coins would be considered classic, it might have a more knowledgeable audience here.  |
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Pillar of the Community
United States
1005 Posts |
Acoustic microscopy has been shown to reveal worn off dates/details by imaging the internal strain in the metal imparted by the original strike. Unlike acid etching, it is completely non-destructive.
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Bedrock of the Community
Australia
21786 Posts |
I am guessing with this suggestion:
Has anyone tried polarized light?
All you need is a light source and a polarizing light filter -
perhaps sunglassed may do the trick.
To prove the light filters are polarizing, test a pair of filters at 90 degrees axially to each other. The light source should be completely blocked out.
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Bedrock of the Community
United States
20753 Posts |
The way I look at it is if you can't see the date, pass on it. Finding a date by any kind of method except just visual is not worth putting in my Albums.
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Pillar of the Community
United States
8715 Posts |
 with just carl. I don't get dateless coins to begin with, in general. |
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Bedrock of the Community
United States
17884 Posts |
Quote:
Has anyone tried polarized light?
All you need is a light source and a polarizing light filter -
perhaps sunglassed may do the trick. Might work but I would suspect it would work better with certain specific light frequencies so just a general "light source" probably wouldn't work very well. I would also think different frequencies would work better on different compositions. Quote:
I don't get dateless coins to begin with, in general. So if you had a dateless 1916 SLQ you would just send it to the scrapper right? |
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Pillar of the Community
United States
772 Posts |
Quote:I have never experimented with revealing dates, but I did recently run into this response on another topic (concerning SLQs): http://goccf.com/t/244823#2834495 I had read that thread as well... I jumped right on board and got myself some silver testing solution. (Nitric and muriatic acid mix) by JSP. Worked on every Standing Liberty quarter I used it on. I've been meaning to add a detailed post to that thread, but haven't had time. It does work though. Stay tuned.  |
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Pillar of the Community
United States
8715 Posts |
Quote:
So if you had a dateless 1916 SLQ you would just send it to the scrapper right? No, I would not. By "I don't get dateless coins to begin with, in general" I don't mean I would pass up a 1916 SLQ with no date, I mean I would not purchase a dateless coin (that cannot be determined whether valuable or not without a date) and attempt to reveal the date. Example: I found a dateless Type II Buffalo nickel for sale, I wouldn't purchase it in the attempt to reveal a possible key date. |
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Pillar of the Community
United States
1005 Posts |
I really doubt polarized light would work at all, in the visible there's no penetration through metal so unless you did surface preparation like etching it would just look like a mirror no matter the polarity.
Conder is right that your frequency would need to be specially selected, I am thinking ultra high frequency like x-rays which have decent measurable penetration through coin-like thicknesses of metal and can be used to image internal structure. Much more hazardous than acoustic techniques though.
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Replies: 10 / Views: 2,118 |
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Posted 11/05/2018 01:40 am
