How to tell if a coin is a Re-punched Mint mark (RPM)
Prior to 1990, the US mint used to take the working dies that made coins and added a mintmark to those working dies. If the coins were minted in Denver, they would add a “D”. If the coin was struck in SanFrancisco the US Mint would add a “S” to the working dies.
The Re-punched mint mark (RPM) has been deemed as a “variety”, since the US mint employee added an intentional, additional strike ( or more than one) to the working die that is making the coins.
Occasionally, the US Mint employee would use a small hand punch and a mallet to add the mint mark. The mint employee would examine the initial strike using a magnification eyepiece. Sometimes the inital strike using the mintmark punch and mallet was insufficient and an additional harder strike would be needed. Then that particular working die would have a re-punched mintmark (RPM).
So how do you tell a coin has a RPM ? It usually can be seen under magnification. There is a wide variety of RPM’s out there. Some RPM’s can be very hard to see. Others are very obvious. Let us review some of the RPM’s out there.
If the mint employee added a mint mark and then examined the punch to discover it needed to be struck one more time, it would add a second mint mark. If the mint employee placed the mint mark real close to the first strike, this would leave a single split serif which can be be seen on the top , bottom or both tips of the “D”. It’s the human error in this procedure which makes the coin a desirable variety.
If the Mint employee strikes a mintmark into the working die once, then an RPM does not exist. It has not been “repunched”, meaning more than once. At that point its a normal mintmark.
How is a D over D (D/D) or S over S (S/S) Re-punched mint mark (RPM) created?
If the Mint employee strikes the mintmark onto the coin twice, a RPM is born. There may be a single, split serif located at the tips of the mintmark. This is usually referred as a D/D or an S/S.
How is a D over D over D (D/D/D) or S over S over S (S/S/S) Re-punched mint mark (RPM)created ?
Should the Mint employee strike the mint mark onto the coin three times, a RPM is born. This should result in the tips of the mint mark to have two split serifs. This is usually referred as a D/D/D or an S/S/S.
An RPM exercise using your fingers.
Think of it this way.
Put two fingers up together. For a moment think those are a mintmark. See the bottom valley between your fingers? if you have a D/D or an S/S you may see just one valley between each mint mark.
Hold up three fingers. How many valleys do you see at the base of the fingers? You should have two valleys. That is what you may see on a RPM that is a D/D/D or a S/S/S.
There is much to learn about Re-punched mint marks
Think we are done about RPM’s ? Nope. In a future post we will talk about why some RPM’s are not added to the CONECA database.
We will also talk about how a RPM is designated as North, South, East, West, CCW CW, horizontal, over mint mark (OMM) and other possible designations.
Until next time, I hope you enjoyed this post in our Educational series.
A few years ago, I was frantically buying Proof Lincolns for customers who said they would be coming to the VNA show in Fredericksburg, VA and would like to pick up some proof Lincoln cents from me. I decided to purchase a few handfuls of rolls of proof Lincoln cents to fulfill other orders I had received.
So when the rolls got here, I opened them up and carefully looked a few of the top coins on each roll to see the average quality. I then set the rolls down next to….. a Cherry Pickers Guide. I decided, what the heck. I put on a white glove and started looking each proof coin in the rolls.
Doubling easily seen on “IN GOD WE TRUST”
When I was in the 1971-S roll, I had to do a double take. I looked at “IN GOD WE TRUST” and I could clearly see the doubling. That “cookie cutter” looking line almost down the center of “IN” is typically what a doubled die looks like. Some devices ( letters numbers or objects) can show die doubling a little stronger or weaker, depending on the doubling on the working die, the strength of the strike onto the planchet and a host of other variables.
Looking at “GOD” I was finally convinced this was a doubled die. In the Example below, the word “GOD” is clearly doubled. When the working die was made, both impressions from the master die onto a working die that struck this coin were at the same depth, only slightly off clockwise. You can see how far off by looking at the word “GOD” below.
Notice how strong that cookie cutter line looks. It’s at the same height of the remainder of the letters. There is no damage associated with the doubling, so that eliminates the possibility of mechanical (worthless) doubling. There is a presence of some notching especially at the top of the “G”. That’s a good sign that the coin is truly a doubled die as well.
We looks especially strong which can be unusual. The “W” is usually pretty weak and the “E” usually shows a separation near the tips of the “E” . This one shows a different look. You can clearly see the “cookie cutter” lines within the “W”. The same holds true with the “E”, although the lighting would not allow me to get both letters on the same quality. If you look at the “E” at each leg at the bottom you will see a slight notching. Additionally the “cookie cutter” line can be seen through the vertical part of the “E” as well.
The word “TRUST” is too wide to display in a single view. If I try to use a lower magnification, the letters, the outer letters (the “T” and “T”) actually become a little fuzzy since they are not closer to the middle. So let us do it this way.
“LIBERTY” shows a moderate doubling
And lastly, “LIBERTY” It does have some doubling, but at this point in taking photographs and adjusting the lighting on every photo, it was getting late and I had my fill of trying to make this work. You may be able to make out the “LIBE” and part of the “R” with that “cookie cutter” style doubling.
Well, thats about it for the spectacular shots, being that this 1971-S Lincoln Proof Cent, DDO-004 is in an ANACS slab. I think it took me about 2 hours to successfully get the photos I did. The slabs tend to bend light in the strangest ways some times.
This coin will be available at a coin show we attend, or on our sister web site called https://errorcoincollector.com where we will list all of our errors and varieties for sale.
Look what this Denali state quarter initially looks like- then think again.
I have quite a few coins scattered in buckets at the location where we store things. On my last visit, I threw a bucket of these coins into my truck and headed home. Last night I was restless so I decided to dig into this bucket and look through a few of these coins. I remove a state quarter that some one had wrote “doubling on EPU”. It’s a 2012 Denali State Quarter to be exact.
I put the coin under the microscope and adjust it until I see the word “UNUM”. This is what I see.
Hummm that looks interesting, does it?
I decided to look around the rest of the coin to see what I could. Although in my mind, these sort of things have been debunked by many an expert as shelf doubling, and I will get back to that in a few.
I move the coin over to EPLUR and look at this area as well.
I see something around the PLU, especially the “P”. I decided to deep dive into this coin just for the fun of it and see what kind of photos I could get. Here is a closer photo of “PLU”.
I wanted to get a closer look at the “UNUM” again. It looked to be the area on the coin which this condition appears to be the best to see. Below is a photo of the “UNUM” area once again.
So, it almost ( the key word here) looks like a doubled die. But in the two photos above kind of contradict themselves. In the “PLU” photo, we see some sort of doubling to the north side of the letters. The “NUM” photo directly above, we see doubling at the southern part of the letters. Now thinking logically, this has two possibilities. Either we have a die that was impressed three times, having an impression, then a weaker one to the north and another to the south or, we have mechanical doubling.
Like I said, I dove deep into this coin. I wanted to see what I could all the way up to the maximum magnification I could get to see if there were any additional clues.
When I look at this “U”, all logic pointing towards a mechanical doubling seems to go out the window. I can see a doubling on the “U”. Look at what I labeled “Grain”. I can see lines across the middle part of the “U” and they do not wiggle or falter in any way. Does this prove it to be a doubled die? Or, are these lines simply “skid marks” ? Hold onto that skid mark comment for a few minutes.
NOTE: One thing I try not to do is move the lighting when I am taking a series of photos at a particular magnification. I do move the coin, and I try to place that coin at the same angle to the lighting as possible. This way a proper comparison can be done. Later if I need other photos, I move whatever I need to move and document the name of the file accordingly.
Ok, the “N” does not see as strong as the “U”. I do see grain lines on parts of the “N” but they are not as convincing as they were on the “U”. People normally would go back to the drawing board as logic is almost in a chaotic state at this point. Where’s the roller coaster sound effect when you need one?
The second “U” in “UNUM” goes back to the same condition at with the first “U”. It looks pretty convincing.
And lastly, the “M” in “UNUM”. The “M” looks a bit different. I see the doubling equal on both legs of the “M”. But, in the center “v” of the “M”, there is hardly any supposed doubling at all.
Ok, let’s let the coin out of the bag per se. With some, if not all of the State Quarters, the side that has the date on it the letters and numbers along that shelf like ring around the outter edge are “INCUSED“. What does incused mean for a coin like this? It means that the affect that is applied has the letters and numbers dug into the coin, vice them being raised. One of the neat things about the State Quarters is that they have both.
The side which depicts George Washington has raised letters and the side that depicts the Denali has incused letters.
Many coin professionals and experts believe that this doubling effect is machine doubling. As the letters of the die come in contact with the metal and puncture the surface, that initial force where the die meets planchet causes either the die or the planchet to shift ever so slightly. This would cause some of the letters and numbers to be a little more elongated than others. That is probably called “skidding” for most, then as pressure is applied it finally reaches its proper depth, and then the coin is ejected out to be bagged.
Also remember that this is a mechanical process. Dies are placed in machines by humans. The dies are carefully adjusted to make sure they operate correctly but, you cannot account for the tolerances in the machine behavior nor the inaccurate tolerances of the human eye and hand adjustments as the dies are being placed into the machines.
Typically – in the “Old Days”, a true Doubled Die more than likely will show split serifs or a notching when a doubled die was present. Typically, the old time doubled dies also had the doubling at or near the same height on both impressions of that working die.
This particular coin has the “doubling” almost exactly on top of each other. Also remember the newer way to make working dies is with a single squeeze technique, rather than the old time multiple impressions on a die.
In the case of the coin above, I strongly ( I think, LOL) believe that this is a case if “incused mechanical doubling”.
In this case, I had purchased three bags of Denali state quarters from the US Mint. I have these rolled up and in safe keeping. maybe on my next trip out to the safes, I may take a couple of rolls of the Denali’s out to see if I can locate a few more examples.
Things like this need to be approached logically. Some that are on the edge and might be discovery pieces should be sent in to an expert for examination.
This particular coin is interesting, but since it is incused where the effects have occurred, it’s a pretty good bet it’s mechanical doubling, but will be put back in a new plastic flip and placed in a box . It’s become one of those ” Let’s hold onto to this for a while” coins.
Trying to identify this 1904 Indian Head Cent Re-punched Date (RPD)
About a year ago, I bought a Indian Head Cent Roll from a customer. My initial motive behind the purchase was to place them in 2×2 cardboard flips and sell them in the $1.00 bargain bin. Most of these had the appearance to grade Good to Fine, with the majority in the G-4 range. When I got home, I set the roll down by the microscope and pretty much forgot about them for about a month. Then one day when I had some time, I started digging through the roll looking for anything Interesting. I did manage to pull out three decent Indian Re-punched dates. I sent those off to ANACS and they came back confirmed as I thought they would.
Some of these Indians, Man, they had so much crud on them that the only option I had was to try and soak them in boiling water. I Let them sit for 15 minutes and then took a slightly moist paper towel to them. That got about 10-20% of the gunk off and still it wasn’t enough. So I repeated the process but in a different way. I took a sturdy plastic container and lined it with tin foil on the bottom. I placed the coins onto the tin foil at the bottom of the container with the worse side up. I sprinkled a large amount of baking soda on top of all the Indian Cents. With another batch of boiling water, I covered the coins with water about 3 inches deep.
Immediately a cleansing action started, the bubbling was really violent and I noticed a slightly discolored Steam. It stunk, I quickly took the experiment outside on the deck and placed it on the railing and went back inside. I put everything away and returned outside to see how the experiment was coming. After the water had cooled to near lukewarm, I decided to rinse the coins off and paper towel dry them off. About 60% or more of the material came off, and I could see a lot more details on the coins than before.
I looked through all of the Indians, and one of the last ones I looked at, I simply chuckled. Here was a 1904 Indian that looks like it is a Re-punched Date. In the past I have tried to photograph this 1904 Indian Cent but I could NOT get the “04” to show the Re-punched Date.
Tonight I got lucky with the lighting and managed to take these photographs.
The Re-punched Date of the 1904 Indian Cent
The 1904 Indian went from almost unreadable to a better looking Indian Cent. It is not in the best shape, but I was surprised to see how clear the re-punched date stood out. This will be one that I will look for when I am visiting the handful of auction houses I frequent.
For the “1”, I believe I can see a second portion of the left top portion of the foot of the “1”, I also see a faint line which runs from the base of that foot up to the flag of the “1” .
For the “9”, at the bottom of the “9” and continuing to the outer right hand edge is some relatively bold impression of the lesser punching.
The “0” seems to be the least affected in the Re-punched date. There is only a slight impression lby the weaker punching to the bottom right hand side. The most impressive digit of the Re-punching is the “4”. The photo shows a second impression from the tail crossbar of the “4” all the way to the top of the “4” . If you look closely at the top of this “4”, something weird is going on. I can clearly see a lower flat top style “4”. The top impression of the “4” at the very top, shows a shorter “4” and the peak is at an angle, probably close to 45 to 60 degrees.
Now will come the fun part. I attempted to attribute this coin prior to posting the photos and I have not yet found a match for this Re-punched Indian cent from 1904. I am in no hurry, eventually I will find a match.
1883 RPD showing a secondary impression of the date
I was on a popular Auction House looking through the merchandise when a PCGS slabbed Shield Nickel was on the list. I decided to take a second look at the coin. The auction house photos were pretty bad. I managed to plug in the certification number to find out that this coin was purchased from another auction house in the Spring of 2020.
The 2nd auction house photos were a bit more clear and I decided to purchase the coin even if PCGS says it was cleaned. My intent for this coin is to use it as a conversation piece at some of he upcoming shows.
When the coin arrived, I took it to the microscope. I am going to take photographs with a Canon Rebel T3i and a special lens that is inserted into the eyepiece. Here is the result of the repunched date on the 1833 Shield Nickel:
Additional photos of the 1833 Shield Nickel with a Repunched Date (RPD)
The Microscope I own is Trinocular meaning it has the potential for 3 eye pieces. The 3rd eyepiece is where a special microscope camera resides. It’s a 14MP camera and through some software it is ported to my PC. I’ll upload a few photos of the date from this 14MP microscope camera below.
The extra base of a “1” is evident in between the primary 1 and 8. I think I see something at the toppart of the “8” as well. The pick up point (PUP) for this coin is the weaker “1” located between the predominant “1” and “8” in the photo below.
I then decided to shift one number at a time. I wanted to compare the “88” to see if there was the same sort of issue at the top of both “8’s” and I can clearly see that there is.
The last two numbers “83” also look intriguing. You can almost see that dash of a line in both the “8” and the “3”. This could be the top of the “original” date punching. I have taken the the time to take a full date photo and match up the lower 1 to see if it would make sense to see parts of the original date within the predominate date punching. To me it looked like a winner.
This will offer a few hours of conversation at the next show we plan on attending. The 1883 Shield Nickels with Re-Punched Dates are not that expensive when compared to the 1833 Shield Nickels with the 1883 over 2 over date.
Interested in seeing this 1883 Shiled Nickel with a re-punched date in person? We are looking forward to attending the VNA coin convention in Fredericksburg in September. We set up on Thursday the 24th of September in Fredericksburg, VA at the Fredericksburg Convention Center off Carl D Silver Parkway. For more information about the show and whether it will be allowed through this COVID pandemic, please visit www.vnaonline.org
A nice 1899 Re-punched Date and a nice coin as well.
Every once in a while, I manage to look through many auction houses to see if something appeals to me. I recently had a handful of Indian Cents come back slabbed and attributed as I self attributed them myself. I had a much lower grade of this 1899 RPD FS-301 S-1 (011.7) and although it was in a lower grade I could clearly see the Re-punched date. As a matter of fact, I believe the lower graded coin has a bit more separation than this currently unslabbed version I am examining now.
Auction house photos of 1899 Indian Cent RPD FS-301 S-1 (011.7) not the best
The Auction House photos of the 1899 Indian Cent RPD FS-301 S-1 (011.7) were not the best. I was pretty sure I could see the doubling below the “8” . The auction photos showed something within the hooks of the “9’s” but I was not certain it was doubled.
I decided to give it a shot. Here are the photos I took of this 1899 Indian cent Re-punched date, FS-301, Snow-1, (011-7d).
Looking at the 1899 Indian Cent RPD FS-301 S-1 (011.7) a little closer
I took the coin to the microscope to attribute it and make absolutely sure it is what it is. There were just two re-punched dates that year as far as I know, at least two that are recognized by the major grading companies. Have a look at the date and see if this is a 1899 Indian Cent RPD FS-301 S-1 (011.7).
Looks pretty convincing to me. It looks better under the scope than in the full coin photo since the cooper red color seems to make the RPD blend in with the rest of the coin.
Looking at Population and Prices.
For the 1899 Indian Cent RPD FS-301 S-1 (011.7) :
PCGS has this valued at $275.00 in MS-63 and $400.00 in MS-64.
PCGS has the population of this coin as:
Two (2) – One in MS-64 and one in MS-65
NGC on the other hand, does not list the FS-301, but lists FS-302.
For Sale at the VNA
My plan is to have the coin slabbed and the attribution authenticated. You will have until Sunday morning at the VNA convention in Fredericksburg VA to take it off my hands. The VNA convention in Virginia happens near the end of September. You can find us at the front tables all the way to the left as you come in the front door.
1885 MS65 Deep Mirror Proof Like & 1899 MS64 MS64 Prooflike
I have just received two more Top Shelf Morgan Dollars. I consider these Top Shelf Morgans for a few reasons. Let’s look at the over all Population numbers for these coins !
1885 MS-65 Deep Mirror Proof Like Morgan Dollar
Total DMPL Graded: 1,258
In MS-65 DMPL : 198
Graded Higher: 63
Total DMPL Graded: 2,111
In MS-65 DMPL : 354
Graded Higher: 142
CDN Retail Price Guide: $1,220.00
I was like, wow, she is a beauty. Not a lot of hits on her cheek and it looks overall appealing. For the population numbers of this coin, there are only 205 total (from NGC and PCGS) that are higher. Pretty impressive since there were 3,369 candidates.
1899 MS-64 Proof Like Morgan Dollar
Total PL Graded: 198
In MS64 PL : 86
Graded Higher: 24
Total PL Graded: 426
In MS64 PL :159
Graded Higher: 94
CDN Retail Price Guide: $645.00
It is amazing to see how incredibly affordable these Morgan Dollars really are. I was taken aback by the 1899 MS-64 PL Morgan. I had to do a double take and check the population numbers again. Why doesn’t this coin have a 1 or 2 in front of the retail price? The population for the PL designation is super low, in my opinion.
Processed 117 BU Lincoln Cent Rolls. Here’s what we found.
I called a 3rd party source since I knew they had a collection of Lincoln Cent rolls they were looking to sell. After a brief call I found out they had (17) rolls of 1957-D, (50) rolls of 1960-D and (50) rolls of 1961-D Brilliant Uncirculated Lincoln Cents. We haggled a brief moment for a price and it was a tad over $400 USD , shipped USPS priority mail.
I paid and waited a few days. I received an email saying the Lincolns were on the way by USPS priority mail. When the package arrived, I opened the 40 pound package to find out the 1957-D and 1960-D were in old school rubber/plastic style tubes. These tubes over time constrict around the rim of the coins and some of them can be a challenge to remove from the tubes.
No problem. Two years ago, I had purchased a 100 roll bag from a fellow dealer and in there were over 60 of those rubber/plastic tubes. What I did was get a 15 pound portable vise and a medium size pair of Vise Grips. The vice is used to hold the tube, but not too tightly. The Vise Grips help in the removal of the tube cap. Once the cap is removed, I take the tube out of the portable vise. Then comes the tricky part. If you hold the opened tube at a 45 degree angle and lightly tap it on the flat part of the vise on the back, the coins will loosen up enough to eventually come out. Sure some rolls are just plain stubborn. But in the end, all of the coins are out. In some instances, the bottom coin or a few of them would not fall out of the tube. I’d hold the tube upside down on the flat part of the vise. I’d give it a pretty hefty hit with the vise grips at the bottom of the roll, enough to see spider cracks. This typically worked, slightly jarring the coin(s) enough to where tapping eventually moved them down and out of the tube.
The First of many types of 1957-D Doubled Die Obverses
I started with the 1957-D Lincoln Cent Rolls. Most of the cents I looked over quickly and mainly just the obverse. I went to VarietyVista so I could take a look at what types of Lincoln Cent re-punched mint marks (RPM’s) and what type of doubled dies (DDO/DDR) could be in the rolls. I started to prcoess the 57-D Lincoln Cents and eventually had to stop and do two rolls over. I think I found a “LIBERTY” doubled die.
An important thing to remember is, although this may look like machine doubling, it is not. Machine doubling ( aka strike doubling) will take away parts of the letters and devices on the coin. Doubled Dies typically will leave a cookie cutter style lines and may also make the area slightly bigger. In classic doubled die fashion, you should be able to see notching on some parts of where the doubling is on a doubled die coin.
So, in a nut shell, take a look at this handy dandy chart !
Photos of the first Doubled Die
I use a lot of lighting when I am using microscopes, so it is relatively easy to spot something like this. On the other hand, lighting is THE number one issue when taking photos of coins. Every coin can be different in respect to the amount of lighting and angle it needs to get a half decent photo.
I quickly looked towards the date. I thought since there was a possibility that LIBERTY was doubled, that the date may show a hint of doubling as well.
The photo above, the “19” show some slight notching. Without taking a lot of time to get the lighting just right. The YELLOW arrows show some mild notching.
The blue arrows signify two die markers that were common in every one of the six or so doubled dies I found for this group. The top blue arrow shows a circular die chip just above the one. The lower blue arrow shows a die scratch that runs from just below the doubled die notching on the “1” to the curl of the “9”. Look at the photo below for a better look at the die scratch.
I can clearly see the notching on the “19” under the microscope. I spun the coin upside down and took a photo. It is evident on the “1” but much easier to see on the “9”. The “57” is pretty minor and difficult to get a nice photograph without magnifying it way too big.
Moving onto ‘IN GOD WE TRUST”, I looked over IGWT pretty good and the only evidence of doubling is here.
One Doubled Die Obverse done
Once I was done with the 1957-D Lincoln Cent rolls, I decided to separate the doubled dies into different tubes. When I separate any type of varieties, I always look for some sort of die marker that is common on each coin. By doing this, it makes sorting A LOT easier.
How die states work on a coin
For the markers on the die, its best to try to find a marker or two that is on the same side the variety is on. At any given moment, they may replace the other die which may throw your attribution off. As a last resort, sure, use the other side of the coin if you need to. On this coin, if you look at the “19” photo above and find the blue arrows, you can see a circular die chip and a die scratch that were evident on each of the coins I grouped together in its own tube. Now, these die markers can fade over time. That means another marker may take the place of these two. If I find the same doubled die with different markers, it means the Die State changed. There are different stages or states a life of a die goes through. Typically they are Early die state, Medium die state, Late die state and Very late die state. Die markers for every coin made can change and some times, the same die state can look a little off in respect for markers – striking coins is not an exact science.
Two other 1957-D doubled dies that I attributed
Now that you have a general Idea of how I attributed and sorted out the first group of 1957-D doubled dies, here are the photos of the second and third Doubled Dies I have done so far.
For the second 1957-D Doubled Die Obverse (DDO) above, the only thing evident was LIBERTY and “19” of the date. The uneven lines on the “19” are stronger than they appear in this photo with the temporary lighting.
Third 1957-D Lincoln Cent DDO
The third 1957-D Doubled Die Obverse is the one that shows the most doubling so far. I do have others to attribute, but these three give you a glimpse on how I personally process and attribute all of my varieties and errors.
A re-punched mint mark, or RPM, is a coin that shows two or more mint marks on the same coin. This was caused by human error in the punching of the mint mark onto the coin die . Before 1990, a U.S. Mint engraver manually punched the mint mark into each individual working die.
Occasionally, due to human error, a die would get two or more punches of the same mint mark, sometimes in almost the same location, and sometimes at 90 or 180 degree rotations. Some times the Mint engraver would catch these defective working dies before any coins were produced from them.
A working die that had multiple punching of a mint mark would strike coins with multiple impressions of the same mint mark letter. Such specimens are called re-punched mint marks, or RPM’s. In the Coin Collecting Hobby these Re-punched Mint Marks (RPM) are very collectible.
When the Mint started using mint marks (letters) in the early 1800’s to identify the various branch mints at which coins were being struck, the mint mark was hand punched into the working dies that would be striking the coins. It was the last portion of the design to be placed on the die. These mint mark letters are as follows: D for Denver, S for San Francisco, CC for Carson City, O for New Orleans, P for Philadelphia, and W for West Point.
A Mint engraver would take a thin steel rod (punch) that had the mint mark engraved on one end and hold it in place on the working die where the mint mark was to be applied. Using a mallet he tapped an impression of the mint mark into the die.
In most cases it was necessary to strike the punch more than once with the mallet in order to leave a satisfactory impression of the mint mark in the die. When the multiple mint mark impressions are from the same mint mark (a D punched over a D, or an S punched over an S), the variety is known as a Repunched Mint Mark (RPM) variety.
Re-punched mint mark terminology
The reference of D/D is used to refer to a “D punched over a D.” Likewise, S/S is used to refer to an “S punched over an S.” So in today’s modern coinage, the most affected mint marks with RPM’s would be the D (Denver) and S (San Francisco) mint marks as they are the mint marks most familar to the collectors.
When people describe mint mark punches, a direction may be implied the D/D or S/S mint marks, such as D/D North or D/D West. When a direction of an RPM is given, that direction refers to the direction of the weaker mint mark punches. The weaker mint mark punches were the first to be punched into the working die and did not penetrate as deeply in the working die. Eventually a stronger primary punch would be the deepest impression in the working die, completing the addition of the mint mark symbol and creation of the RPM on that working die.
A Doubled Die is a term in coin collecting used to refer to doubling in the design elements of a coin. Doubled dies can appear as an outline of the design or in extreme cases, having design elements and dates appear twice in an overlapping fashion. Doubled dies can be seen on the Obverse or Reverse of the coin – or both ! They are commonly referred to as Doubled Die Obverse (DDO) or Doubled Die Reverse (DDR).
What are Doubled Dies worth ?
Doubled die error coins can fetch significant prices when they are noticeable to the naked eye or occur in a popular coin series. A few examples are the 1955 doubled die Lincoln Wheat cent, the 1969-S doubled die Lincoln Memorial cent, the 1972 doubled die Lincoln Memorial cent, the 1964 doubled die Kennedy half dollar, the 1961 doubled die Franklin half dollar to name just a few.
In the coin collecting world, proper terminology for this occurrence includes the letter ‘d’ at the end of the first word, hence “doubled die”. The term “double die” without the first word ending in ‘d’ is not proper numismatic terminology.
How are Doubled Dies created?
Doubled dies are created when the master die imprints an additional, misaligned image onto a working die. Its the working die that has two or more pressings, not the planchet. A working die with several misaligned pressings is taken to a press where coins are made with that working die.
The different classes of Doubled Dies
There are many ways this misalignment of devices can occur, which have been grouped into eight classes:
Class 1 Doubled Die, Rotated – Results when the working die receives an additional pressing from the master die that is misaligned in a clockwise or counterclockwise direction.
Class 2 Doubled Die, Distorted – Results when the master die design moves toward the rim between hubbings.
Class 3 Doubled Die, Design – When a master die bearing a different design stamps a die bearing another design.
Class 4 Doubled Die, Offset – The working die receives an additional pressing that is misaligned in an offset direction.
Class 5 Doubled Die, Pivoted – The working die receives an additional pressing that was misaligned via rotation with a pivot point near the rim.
Class 6 Doubled Die, Distended – The working die receives an additional pressing from a master die that was distended.
Class 7 Doubled Die, Modified – The master die is modified between the working die’s pressings (e.g., a design element was chiseled off).
Class 8 Doubled Die, Tilted – A working die and/or master die is tilted during a hubbing.
Doubled dies are a result of the way in which in the United States Mint dies are created. Before 1997, die pairs (hammer die and anvil die) were made by hubs that contained the raised design elements that were intended to appear on the coin. The blank dies were heated (to soften them) and then were pressed against the hubs to transfer the design from the hub to the working dies.
Often, one impression was not enough in every case to transfer the design elements from the hub to the die, so multiple impressions were required to transfer enough of the design. For this reason, after the first impression was made, the die was reheated and prepared for a second impression.
The mint workers would try to use guides to align the hub and the working die perfectly to prevent overlapping, or a doubled die. If the die was acceptable within the mint standards, the working die would be put in a press and coins would be minted. If the engraver thought something was amiss, they would stop the press and investigate. A lot of variety coins have escaped the mint prior to 1996.
It is when mint workers failed to align dies properly during this process that doubled dies were produced. In many instances three to four impressions were required, which could but rarely led to tripled and quadrupled dies.
In summary, prior to 1996, after each impression, a heated working die is removed and checked to see if the entire design and its details were successfully transferred from the master die, to the target working die. A doubled/tripled/quadrupled die is created if these multiple impressions pressed onto the working die were not properly aligned. If the die was acceptable and within the mint standards, the working die would be put in a press and coins would be minted. If the engraver thought something was amiss, they would stop the press and investigate. A lot of variety coins have escaped the mint prior to 1995.
Note: you will see HUB used in place of master die in may locations – it’s the same thing.
New way to make working dies but doubled dies are still being created
Modern coining methods have greatly reduced the number of these varieties due to the use of a single squeeze hubbing method during die creation, but doubled dies in modern United States coinage are still occurring.
With this new die making process implemented after 1996, dies only require one impression of the hub to transfer all of the design from the master die to the working die. But it has been discovered that the pressure created is so great, that some working dies tend to slightly rotate during this process.