Because I think it's PVC residue. And the TPGs will not slab a coin that has PVC residue on it. Or at least they sure didn't use to. Today, apparently they will.
Isn't the reason that they won't because the PVC will eat at the coin eventually downgrading the coin?
Gold sometimes develops verdigris, and yes they will slab coins with verdigris on them. But when they do, there is never very much of it, just a little here and there. That coin has green all over the place - both sides. So the chances of it it being verdigris are pretty much nil. Therefore the green must be something else, and the most likely candidate is PVC residue. And neither NGC nor PCGS will slab coins with PVC residue on them - or as I said at least they never used to. No Grades PCGS will not grade and encapsulate any coins with the following problems: 82 Filed Rims Rim(s) and/or edge is filed. 83 Peeling Lamination Potential for sealing damage. 84 Holed and/or Plugged Any filled or non-filled hole. 86 No Opinion – our experts are unable to determine a coin’s authenticity – fee not refunded 87 Not Eligible For Service Selected – the coin is too valuable for the chosen service level – fee refunded 90 Questionable Authenticity – the coin is most likely a counterfeit. 91|N-1 Questionable/Artificial Toning (or Questionable Color for copper) 92|N-2 Cleaned – surface damage due to a harsh, abrasive cleaning 93|N-3 Planchet Flaw - Metal impurity or defect in the planchet – depends on severity 94|N-4 Altered Surface - Whizzed, harsh cleaning, thumbed over (using a pasty substance to cover defects or alter the appearance). 95|N-5 Scratch - depends on the severity of the scratch. Rim dent. 96|N-6 No Service – coins we do not certify (i.e. medals, some privately made issues, etc.) or cannot certify (i.e. over-sized coins) 97|N-7 Environmental Damage – i.e. corrosion, coating (lacquer), excessively heavy toning, etc. 98|N-8 Damage – deliberate surface damage, i.e. graffiti, spot(s) removed, etc. – depends on severity 99|N-9 PVC (Poly-Vinyl-Chloride) – a plasticizer used to produce vinyl that will leach out of the holder and onto the coin, eventually damaging the surfaces. No Grade Description 90 Not Genuine 91 Artificial Color 92 Cleaning 93 Planchet Flaw 94 Altered Surfaces 95 Scratch / Rim Dent 96 Refund - No Service 97 Environmental Damage 98 Damage 99 PVC
From looking at pictures of pvc damage, it appears to be more of a green haze, not green debris stuck in crevices. This is why I don't think it is that.
It almost looks like Play Doh... I've never seen anything like this on a coin. What do you think it is?
PVC residue has many different looks and many different colors, the variables are almost limitless. It can be clear, almost invisble; it can be milky looking; any shade of green, brown, and even white just to name a few. And it can be of several different textures ranging from slimy even to the touch, dried and hard or even flaky. It all depends on how much of it got onto the coin and how long it has been there. This particular coin has been cleaned, not harshly cleaned - cleaned, in an effort to remove the PVC residue. Unfortunately they didn't get it all and what you see is what remains. Now, let's say you're right, let's say it's not PVC residue. The fact remains that it IS something, it is a foreign material on the coin - environmental contamination of one kind or another. That much cannot be denied. And since it is there, the coin cannot be graded.
So that's why the seller of the 1878-S in ANA-PNG slab didn't take my offer! He had a few other fairly rare dates....but pricier.
More MS graded Indian with dirt... I think the graders disagree with you that they can not be uncirculated (CAC too). http://www.ebay.com/itm/1925-D-2-50...378506?hash=item2a7bc8b8ca:g:Fj0AAOSw4CFYryib http://www.ebay.com/itm/1925-D-2-50...266124?hash=item489947d1cc:g:SaIAAOSwdGFYry94
Uhhhhh - "dirt" is not considered environmental contamination. You'll find plenty of slabbed coins that have verdigris on them too, that's not environmental contamination either.