The idea you have about a mixed section of questionable coins is fine. However, that was tried and it failed. The problem was "Who places the items in that classification?" Who makes the decision?
The fraudulent sellers will not admit their coin is bad even if they know it is and these are the people who threaten
ebay with lawsuits under all sorts of pre-texts.
If you follow this forum you will see that coins of disputed originality are posted all the time. On average VERY few of these get a unanimous verdict - even here where you would expect people to be knowledgeable.
The people at
ebay do not have the experts on staff to decide about any item. The number required to completely police all posts would be astronomical compared to present staff levels.
On the Coin Review Committee which reported to
ebay Trust and Safety we had seven accredited "experts" with an average of 40 years experience in the coin business. There were six devoted primarily to
US coins and I was the World and ancient expert.
Do you have any idea how many coins appear on
ebay every day? The answer is about 600,000 - these are spread over intervals of 1 day upward but average 7 days. That averages out to 80,000 to 90,000 a day.
Lets say all 7 experts could work independently and ONE opinion was sufficient (which it is NOT according to the lawyers) that is somewhere between 11,000 and 13,000 coins per day every day 365 days a year.
How long does it take for an expert to determine authenticity? Thirty seconds? What if every coin needed to be documented adequately to withstand a later lawsuit? Would the number rise to 1 minute - 5 minutes?
Even if it was possible for a human being to review each coin and if only one person need to do so instead of 7 and if this could be done at the rate of 2 per minute for an entire work day with no brakes - each person would have to spend 92 hours a day - 7 days a week to do it.
Since work production studies in many companies has determined that actual error free production time averages a 40% efficiency rate in average people (deducting time off breaks, lunch sick days coverage etc.) the workload requires 30 full time employees.
This is just for coins - and is unrealistic because the lawyers have stated that to prevail in court we would need a unanimous vote of several experts for each coin determined to be a bad coin or for an auction to be declared a fraud. The number see as defendable before was seven and a vote had to be unanimous.
So about 210 employees for coins and results would not be perfect.
This is why
ebay decided years ago that the Committee for coins would only review REPORTS made by
ebay members. This reduced the workload to only coins that were reported as bad. It was hit or miss. Then we added "well known frauds" that all members hunted. This worked well reducing the fraud rate to about 3%. But
ebay legal felt the company was too exposed to lawsuit by groups of forgers (Chinese and Spanish) that were preparing to sue because we were not 100% consistent. Some fakes were missed by the report process while others were terminated. This hit or miss pattern was seen as indefensible and as a second line of attack they planned to bring in experts who would attack credentials and the ability of anyone to be sure from a picture.
The next step postulated was a clearing house to review all coins in hand BEFORE they were posted which was logistically impossible unless all experts were in one place and then there was liability and lawsuits charging that coins were switched at the
ebay location - all hard to defend and very time consuming.
I supported a voluntary mechanism that every seller wanting to use
ebay would have to waive their rights to sue but because laws vary in different jurisdictions coming up with an air tight method of doing that was considered IMPOSSIBLE. Again too many lawsuits to defend economically.
They also looked at selling only
TPG encapsulated coins. That was a lead balloon because of the suit that was already filed over the
ebay policy of allowing only 4 companies to be named in titles and descriptions while all other TPGs could NOT be named. Even the issue of allowing or not allowing pictures of the capsules of anyone but the big 4 was reviewed.
Look at this auction
http://www.ebay.com/itm/311258222438 The seller is centles which happens to be the firm that encapsulates the coin NNC. This was one of the guys that sued over his right to post his own slabs. Now in this case, I know the coin is a variety using one die of the Riddell # 237. It is a Contemporary Circulating Counterfeit. I know that but centles has a 99.4% positive feedback rating of 165890. So could we take the coin down? Who pays to defend the inevitable lawsuit?
About a year ago on this forum I posted an NGC encapsulated coin that was found in the same reference book the Riddell # 221 an 1829 Zs AO counterfeit 8 Reales that I knew very well. I had the coin terminated TWICE. I got the unanimous vote of the Committee only AFTER I presented a detailed 5 page report on the coin. In that case, the owner was backed by NGC, Richard Ponterio (now of Stack's and their expert on Mexican coins) and Mike Dunigan who wrote the book on the Cap and Ray 8Rs. They all said the coin was in fact genuine and that I was wrong. My opinion was reversed and the coin was posted a third time. The coin sold on the THIRD posting. It took 8 months but after a considerable review of data by Mike Dunigan and the finalizer for NGC - the coin was ruled a counterfeit in October 2014. EXACTLY as I said after a 30 second initial review.
The coin now in private hands is being sought by NGC who has cancelled the accreditation number and wants the coin OUT OF THEIR HOLDER. Ponterio has still not (at last check anyway) removed from his website database a photograph of a second Riddell # 221 which he posted as an example of a genuine 8R.
It was shortly after the reversal on this coin that the Coin Committee was disbanded - I have asked if that case caused the action and they say no, but the case points out how difficult it can be to authenticate and to gain consensus among experts.
Sorry for the length of the post but this topic has been my focus for many years. I see NO perfect workable system but I will keep trying until I die.