I'm going through my dad's coin collection, I found some odd mint marks and I wanted to see if I am on the right track in picking out the mint mark errors. My first sort of base line example is actually a 1946-D dime. It's not in great condition; the AI app I used puts it at only VF: Here is a closeup of the mint mark and I'm using it as my "normal" mint mark, though does it have a slight counter-clockwise rotation visible at the lower left corner of the D? This is a 1951-D dime (AI gave it VF) that I'm iffy on. The MM appears thicker than normal and there looks like there could be a slight counter-clockwise rotation. However it makes it appear that there was a bigger version of the MM and then a smaller one on top, which I have not found anything about that kind of MM error online. Thoughts? Then I find this one on a 1952-D dime (AI gave it VF). This looks doubled and shifted a little to the SE, based on the small notch visible on the upper right corner of the D (sorry for the pixelization, I cropped it). Is that right? This 1953-D dime (AI gave it XF) is a bit weird. I'm not sure what the discoloration is around the MM but it almost looks like a triple MM with the top smaller one rotated counter-clockwise. I suppose it could only be double but I'm not sure. What do you think? This 1954-D dime (AI gave it AU) has very weak MM(s). On the full coin picture I barely could see it with the camo-like colorization (toning?; also is that AU rating accurate?). But on the closeup, you can just make out the outline of the D MM and then another D MM that looks smaller on top of it, shifted SE based on the notch at the lower left corner of the smaller D. Do I have that right? Last for this post is a 1958-D dime (AI gave it XF). Again, thicker and looks like a slight counter-clockwise rotation based on the notches at both the top left and lower left corners of the D. Do you agree? I'm just looking to see if I am identifying these errors correctly and looking for guidance. Also what is a typical value increase from MM errors like these (I think) vs without? Thanks!
Welcome to CT. Firstly I am not seeing from your images any signs other than die deterioration and circulation wear. The mintmarks were handpunched into the die in those days, so differences in position and slight tilting was absolutely normal. None of them would be errors anyway as their description would be re-punched mintmark (RPM). Just like a variety, the die would have produced thousands and thousands of coins with the identical look until the die was withdrawn at the end of it´s useful life. I would suggest you read up on the minting process and how dies were made, the difference between errors and varieties, and then study the many pages of the same subject on the errors forum pages. There you will see many questions like yours and the answers from the many knowledgeable members here. Happy research and good luck.
Your dimes are all worth melt value. They are well circulated and have hits and cuts on them. The 1946-D Dime is VG at best not VF. Even the mint mark took a hit. The 1951-D mint mark has been flattened from its original minting. Each coin you posted is normal in every respect. Mint marks were hand punched onto the die so there are various types but with millions of each type it’s considered normal. Welcome to CT.
Ah, ok so I guess I used the wrong term. Those are RPMs then and RPMs are not then considered errors... hmm... after some additional searching, it looks like those are just considered varieties? so there is no real value in any RPMs? I found some references online around increased value: A pretty good rule of thumb for value is that as the separation between the mint mark punches increases, the value increases. Is it only specific ones or are sites like these incorrect? I've seen references to some (perhaps modest) value increase but never any guidance on how much. Also I expected there to be little to no value with the condition of these for the base coin itself, it was more about having examples to sort of gut check on.
Also the AI app I used was Coin Snap... I guess it is really only mean to be a starting point for grading but do you think it is so far off that it's not even worth it as a starting point?
There are some desirable mint marks. In 1942 there were 2 different size mint marks from San Francisco mint. I think there is some others, but I only have this one. Again DENVER Struck twice with 2 dies, one a Large Date and one a Small date. They also made a D/D while doing it. These are one of my favorite coins. Whether it was by purpose or not, I do not know. Jim
So far you have not shown any RPM´s, so nothing to "gut check on". As far as grading goes, the only tools you need are, eyeball mark 1, and studying hundreds of graded coins of your chosen denomination.
Well, even a negative result is still a gut check.. However I don't think I get why at least the ones like this: are not an RPM. I understand that you get the "shelf" effect and that is not caused by an RPM or any kind of doubling. But I read somewhere that one way to tell the difference is these kind of notches where the red arrow is because the edge of the 2nd mark exceeds that of the lower "shelf". Is it that yes, because they were punched manually most have some variation on multiple punches and it just isn't pronounced enough to be considered an RPM? To me this seems more pronounced with the notch than this one that is considered to be an RPM (though this one is in much better condition). However I am just a newbie at this... I'm just trying to understand what the difference is.
In 1989 (as I remember) the mint started putting the MM on the die, and MM should have not had any doubling , etc. unless the die itself was damaged to mimic a RPM which was very seldom. I personally am not interested unless it has significant separation, but each collector has their own range, there is no set level such as .1mm, .2 mm, etc. Here is something you might like to read. https://www.coincommunity.com/forum/topic.asp?TOPIC_ID=393987 Jim
You need to read up on re-punched mint marks RPM. YOU NEED TO KNOW THAT FIRST. Earlier coins the mint marks were hand punched. Not repunched
