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craigy

Toning while slabbed

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Not sure how the grading can only be guaranteed for 10 years. I can understand extra toning if the materials chosen  for the capsule contain sulfur or  the capsule is not airtight allowing oxygen and atmospheric pollution to reach the coin's surface. I think most people would expect these issues to be addressed by NGS etc. However the guaranteeing of the grade for 10 years implies extra wear can occur in this time is this to be called capsule friction? Sounds like a ploy by TPGs spruiking for extra business.

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I suspect it is them covering their backsides on the evidence of past degradation seen. If there has been a significant number of cases where toning has changed after 20 years, then you guarantee it for 10. It would be interesting to have an independent view on the long term results of the cooper/bronze cleaning agents used in 'conservation'.

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In my experience (well, bitter experience in some cases!), the key agent in spotting a coin is...….dandruff. Tiny skin flakes are deadly, especially on a proof or lustrous coin if left for any length of time. I always try to check my coins before I put them away after viewing: at least the white flecks show up well at certain angles. Then I dab off with a cotton glove, or if it's still sticking, a very light application of a toothpick.

So if a coin were slabbed with a tiny skin flake on it, further deterioration is likely to happen. And you wouldn't know whether the coin was graded with that spot or not.

I have a lovely 1951 proof set I bought about 20 years ago with fully gleaming bronze, but the penny over the years has developed two small but unsightly brown dandruff spots, both residues spreading from skin flakes which I spotted then removed - great, the most valuable coin of the set as well!

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Dandruff Peter........😵

It could be i suppose as Head and shoulders did not come out untill 1961 :D

How on earth would you be able to tell that is what it is ?

 

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Aka Sebaceous Pete....tiny white and oily flecks, can't be anything else. Not putting anyone off their lunch am I?

If you cut the human element out of coin collecting, it wouldn't be an issue!

 

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I suppose what i meant was how you could tell the difference between dandruff and a tiny bit of something else.

Nearly every coin that has good lustre and seen daylight will show tiny microscopic spots caused by anything that was on the coin.This can clearly be seen from the residue left from a finger print.

IMO Its........ Does it look ok to buy or does the spotting or size of the spot not look pleasing and may develop further in the metal.If it looked ok when i bought it after decades then just store away the best i can which hopefully will prevent any further spotting or toning.

The topic of the thread being about the condition that it was in when put in the slab and should hopefully not start to show spots after or further toning if stored corectly , but there is know guarantee.

Will remember that one.......Sebaceous :D

Edited by PWA 1967

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2 hours ago, oldcopper said:

 

Aka Sebaceous Pete....tiny white and oily flecks, can't be anything else

 

Hi Peter, I think I can help here. I too used to conclude my viewing by dabbing off with a cotton glove. Now I make doubly sure the coins are well out of the way before I start. Hope this helps.

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Some time ago a NGC video was posted that clearly shows NGC graders handling coins with bare hands leaving the subject coin exposed to finger prints, fallout from sneezing etc. and I do not remember  any degreasing proceedure with acetone to remove tis contamination before placing the coin in a capsule. Perhaps this could be the source of contamination that can cause the coin to deteriorate after slabbing.

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10 hours ago, ozjohn said:

Some time ago a NGC video was posted that clearly shows NGC graders handling coins with bare hands leaving the subject coin exposed to finger prints, fallout from sneezing etc. and I do not remember  any degreasing proceedure with acetone to remove tis contamination before placing the coin in a capsule. Perhaps this could be the source of contamination that can cause the coin to deteriorate after slabbing.

Exactly so...I also remember that video on here.

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11 hours ago, ozjohn said:

Some time ago a NGC video was posted that clearly shows NGC graders handling coins with bare hands leaving the subject coin exposed to finger prints, fallout from sneezing etc. and I do not remember  any degreasing proceedure with acetone to remove tis contamination before placing the coin in a capsule. Perhaps this could be the source of contamination that can cause the coin to deteriorate after slabbing.

Almost incredible that they would post their own video showing that. Is it ignorance, arrogance or stupidity?  

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On 3/14/2019 at 9:28 PM, 1949threepence said:

Almost incredible that they would post their own video showing that. Is it ignorance, arrogance or stupidity?  

When you see some of the grading decisions from TPGs it's probably a combination of all three.

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On 3/14/2019 at 11:28 AM, 1949threepence said:

Almost incredible that they would post their own video showing that. Is it ignorance, arrogance or stupidity?  

Just arrogance. The PCGS grading video also shows coins being handled without gloves etc. If you want your coin graded, then it is either PCGS or NGC and you don't have much of a third choice. 

 

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CGS?

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7 minutes ago, ozjohn said:

CGS?

From memory, I think Paulus was shown their grading process once and said CGS didn't wear gloves either. Personally, I don't think they show enough care and some of my CGS slabs have foreign objects inside. 

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On 3/11/2019 at 6:11 PM, Sword said:

"not responsible for problems such as spots, hazing"

Teenagers will be glad to know that

  • Haha 2

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On 3/22/2019 at 9:46 PM, craigy said:

Agreed. It is a great shame. 

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A few years ago I sent some full lustre brass 3d to CGC in Florida.  After something like 3 years I noticed that they'd noticeably darkened.  I also bought a CGC slabbed brass 3d off ebay, which would have been submitted by someone else and at a different occasion.  Interestingly this too subsequently darkened.  The fact that they were from two separate submissions proved to me that it was caused by something independent of the coins themselves.  Although it also seems likely that it is something peculiar to brass.  I should also add that this darkening doesn't seem to be progressive, i.e. they darkened to an appreciable degree (enough to affect value) but have not got any darker since.  I wonder whether this might have anything to do with the fact that CGC holders contain a larger volume of air compared with CGS/LCGS holders.  I also wonder whether it might conceivably have something to do with the Floridian humidity.  

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