Coinbuf

Unless your coins are certified as MS67 or better spend them, they are only worth face value.

Yes it is, I have laid out detailed instructions on how to do it on a previous post on this subject. Here is a link to that post. How to print inventory

It is always best to start a new thread when asking about a new/different coin. Most of your photos are out of focus to see clearly, it could be one of the RPM's listed on Variety Vista, the other explanation is a die chip which was a common issue in the 50's. Have you attempted to match your coin to one of the five RPM's listed on VV? Only one of the listed RPM's is considered significant enough to receive an FS designation, and yours does not look like a match from what I can see, maybe a match for RPM2. Here is a link to the 55-S RPM page at VV if you don't have VV bookmarked. Variety Vista

You are correct that there are many people out there attempting to create colorful coins to fool people and extort money for the pretty colors. Sadly, this does work at times and there are people who fall victim to this area of coin doctoring. Toning is a very deep subject with many nuances, even the TPG's like NGC and PCGS are fooled when it comes to real vs artificial toning at times, I can guarantee you that there are toned coins in both holders that are not natural. Books have been written on the subject of toning; it is a complex area. And toning is different for the different types of metals, and in many cases it is different for uncirculated coins vs coins that have circulated in commerce. It takes a lot of time studying and looking at multiple real and artificially toned coins to develop your eye to spot it. One universal thing which was touched on by @EagleRJO is color progression, in nature colors seldom have hard lines. Think about when you look at a rainbow, those colors blend from one to the other, not one color then bam the next color. Now look at the coins in your palm, notice how the colors are not blending, they look like the colors were painted on like the old paint by numbers that you may have done as a child. Then look at the photo in @Lem E post, notice how the colors on that liberty nickel softly blend from one to the next, no hard lines. Also notice how the colors on the cents in your palm are flat and lifeless compared to the nickel where the colors are more vibrant and have a somewhat iridescent look, this is easier to see in hand but once you know what it looks like you can spot it easier in photos. Real toning will move and react to light as you rotate the coin under a proper light source, where most artificial toning does not, it just lays there and has no movement or life to it. Then again some forms of real toning, like toning that happens to coins in some of the US mint packaging, will have a very different look. That look can simulate the surface of a dry lakebed, with a crackled look to it, totally natural from the mint cello but very different. Toning is a very hard thing to master, I have been collecting for decades and I am still learning when it comes to toning each and every day. That is one of the reasons I like to go the local monthly coin show, not to buy but simply to look and talk to dealers and collectors. After you look at thousands of toned coins both raw and in TPG holders you will begin to develop your eye and see the things that distinguish real from artificial, even if we never fully master toning. I can only speak for myself, and the answer will depend on what coin I am looking for. Personally, I much prefer a bright original red cent vs a toned one when looking for or at uncirculated coins, but for a circulated copper coin my preference is for a nice even brown color. But in even with copper I have examples of toned coins that I find to be extremely attractive, just not something that I actively hunt for. For silver coins I again prefer them to be blast white just as they looked when they were struck, but the older the coin the less I expect blast white. As silver ages it will mellow and tone naturally, no coin can stay as struck unless stored in a vacuum. And here again, I have many toned examples that I find very attractive just not what I necessarily hunt for.

As Lem said it is your collection and you should do what makes you happy when you view the coins. Having said that I truly think that knowledgeable collectors would uniformly use the term "beaten with an ugly stick" to describe the 18-S Lincoln. That coin does not exude original toning in any sense of the word, the coin has been completely messed with or "bonked" as many describe the artificial toning that has been applied to that coin. I can only speak for myself, but I would take a nice light to chocolate brown toned coin over that mess any day.

Hmmm are you sure it doesn't belong to dprince, has his fingerprints all over it. But in all seriousness, this type of garbage is rampant on ebay and etsy.

Meant to post this the other day and forgot, bought this 14-S from the same forum member on the PCGS forum that I bought the 23 posted earlier. Has a nice bit of color, PCGS graded MS63; slab needs a bit of a polish.

Not even close.

Why in the world would you even think this is some type of error. Do you even know what acetone does, I can only guess that you don't from your question. The obvious answer is the coin is stained, maybe buried in the ground, maybe in somebody's pits for a few years, anything but an error. Have you spent any time looking over the reference sites you have been so generously provided by members here, or are you just going to continue to throw everything at the wall to see what will stick. Keep it up and knowledgeable members will start to ignore your posts as a waste of time, which will only leave you with the misinformed members responding. You don't have to have money to read and learn, but you do have to put forth the effort and actually do the work and read and learn.

My suggestion is stick to your day job, there is nothing in your photo to suggest that the coin you have posted is off center at all. If this coin and your 82-D are a display of the knowledge you have learned from you tube you have learned nothing but misinformation. I am not saying this to be mean or hurt your feelings, that is just the cold hard truth.

Honestly, not that bad. Not a crazy nice work of art but still better than the dead presidents we have on our coins.

If there is a large coin show near you that would be a good opportunity to show the coin to an expert or two. Sulivan Numismatics deals in mint errors and does most of the larger coin shows. I don't collect errors myself so that is the only reputable error dealer that I am familiar with, I also like @Fenntucky Mike idea to post it on the CONECA website for additional feedback.

My herd of Buffalo coins is small, but I did recently add a couple of new coins to the corral. The PCGS TV does the coin little justice as the coin is much brighter then it appears and that carbon spot while certainly there looks far more intrusive than when viewed in hand, at least by me as the new owner.

I'm not sure that would be a correct term as we don't know if these are in fact from a die that became damaged, a defective planchet, plating bubbles or just what actually caused this particular effect. If these marks were caused by the rotary dial of the Schuler press I would expect to see curved lines rather than straight lines as any contact to the dies would be as the dial turns to move the next planchet into place between the hammer and anvil dies and discard the previously struck coin into the exit tube. I don't think we are going to be able to come up with a definitive or conclusive answer from just the photos, an in hand examination by an error coin expert is likely needed.

They could indeed be some type of die scrapes, however, if I am not mistaken, the mint was using Schuler horizontal presses at the time this cent was struck. If memory serves, the mint began to convert to the horizontal press in the mid 1980's. That type of press does not have feeder fingers, it uses a rotary dial (similar to an old dial telephone for anyone that is old enough to remember one). So unless I have my dates off and this was not struck on a Schuler press, I do not think this could be called feeder finger damage.

Linear plating bubbles/lines. Super common no added value.

Sweet coins, wish I had a place for one or two.

Not cut off blocked off, most likely by a partial grease fill.