Learning To Identify Cleaned, Buffed, Adulterated Coins...

Thanks so much! Very helpful advice. :O)

DD, to me the IHC looks like there might have been cleaning way back when, there seems to be a slight halo around her feathers. The cent looks more like bag marks or some sort of flow lines of the copper. definitely not cleaned

Agree with the others on the IHP. While it looks great in the pics, that seller has a very bad reputation so I wouldn't trust them. The Lincoln looks more original (notice the luster shine?). I still struggle telling the difference between bag marks and cleaning as well though. I try to look for that blazing luster look however for lower grade coins the luster may be gone due to honest circulation.

The lines on the LMC look to me like die polish lines. A close examination will tell.
Technically, you should be able to tell coin polish lines from die polish by seeing if the lines are incused or protruding.
However, that is often difficult to tell. Instead, check if the lines seem to cross through the devices and if they do see they on the devices. Also do they come right up to the devices out do they stop near them.
Die Polish Lines will often seem to run right UNDER the devices.

dd27, I am working on a collection that has some coins that have been attacked by the Green Monster. I can't reverse the process, but I can keep it from getting worse. Seeing a before and after may help.

The half farthing came out of a PVC flip, where it may have resided for many years.
It got a soak in acetone for about an hour.
Then a soak in a commercial product I'll refer to as brand X, followed by a rinse in acetone and another soak in VerdiCare.
Most of the green came off easily with a soft artist's brush.
The general consensus is that VerdiCare will remove the green if it is not permanent.
It is possible that the light patch on Victoria's forhead may tone more naturally with time.
Not all of my procedures are approved of, but for the more extreme actions, I never work on a valuable coin.
Conservation is when people cannot tell what you have done. Cleaning is when the work is visible and people don't like it. I just made that up.
A search on "cleaning" will give you lots of posts to review. Here is one that shows a few I have cleaned/conserved. Most of those coins cost me about a dime and came from the melt bucket.
https://goccf.com/t/244101&whichpag...rms=cleaning
With experience, I am becoming less aggressive in my approach.
Note the mottled colors on the coin where the crud has been removed. This may give you a clue when viewing coins with an uneven tone.

Cleaned coins sometimes is impossible to tell. Many individuals that sell cleaned coins have been doing so for so long they are becoming experts at this. Many professionals have been fooled by expert coin cleaners. Sometimes it is really tuff to tell. And as to sellers on ebay, you really can not tell by feedbacks or comments. My Son sells on ebay and has many friends fake feedbacks for him. If is easy for dealers to have people send in fabulous commentaries about a seller. You really can not tell by so called feedbacks. YOU just really have to get to know coins, coin cleaning, etc.
I've known many dealers that could not tell if a coin was cleaned or not so for the average person, it gets even more difficult.
On a TV show, The Big Bang Theory, recently a person said "There is no place for the truth on the internet"

I'm no expert, but when an ebay vendor has a lot of coins that have almost exactly the same "look," I figure they are most likely doing something to them. When I first resumed my quest for nice circulated Lincolns, I bought a couple of coins from the teens that I thought were beautiful. The most distinctive characteristic were that they were veeeeeery clean. After I realized that almost all of his offerings looked the same, I decided to go elsewhere.