This month in our 1881-O Morgan Dollar web site we are launching into a study that we are calling "fingerprints" where we plan to use our inventory to examine each die for cracks/breaks and determine the uniqueness. This one will take a long time, so we have our study road map for the next year. There are 47 obverse dies and 18 reverse dies for just the 1881-O series. Not all have cracks and breaks, but most have some. Even though the study is narrowly focus on the 1881-O Morgan Dollar, some of the technical findings will be applicable to all coins containing cracks and breaks. But please remember we are studying only cracks and breaks and largely ignoring other things we know normally go into die identification on purpose. Because VAM 53 is very common in the 1881-O series, and we have a lot of them, it is a good jumping off point. We know that many if not most collectors on this site are not VAMmers, but the discussion should be of interest to any collector who encounters cracks and breaks. We also review a couple of books we read this past month. And to top it all off, we actually have the page up a day early, which I put into the miracle category. http://www.1881o.com/2017-05.html We hope you enjoy the discussion!
Interesting - I am working on the same type of thing using CAD but not just for VAMs but all coin issues. Instead of discriminating based on design deviations attributed to die usage - I am trying to discriminate working dies based on deviations of design attributed to the die manufacturing process. Following are 2 images of the date of an 1881-O Morgan. The date for obverse 34 was borrowed from your website. Hope you don't mind. The other is a random 1881-O Morgan. Don't know what VAM. Drew a line from the tip of the left star to the right star on both. Take note where this line intersects the last digit "1" of the date. PM me if you want to discuss further.
Here are CAD tracings of the two different coins in my post above. There is deviation in the positioning of the six design elements relative to each other between the two obverses. Gives me indication it may be possible to identify all 1881-O obverses by mapping these six design features for each die.
The vertical position of the 81 might vary from die-to-die, as observed, but it doesn't make a useful diagnostic, because it's difficult to see with a magnifying glass. The landmarks (stars) are too far away. Connecting the upper right corner of the 2nd 1 with the most distant point of the first right start might work, too, but would probably have a similar problem of being hard to gauge visually. This does show that there are minor date placement variations in the last two digits for 1883 and earlier Morgan dollars, though, because the first two do not move. Overlay the two and it becomes really obvious.
I agree the diagnostic is very difficult to see with the coin in hand using a magnifying glass but substitute using an image of the target coin instead and that issue goes away.
As Messydesk knows I got into this pretty deep a while back and you might enjoy this page http://www.1881o.com/date_issues.html No problem borrowing the image so long as you site it to me and VSS. Sorry for the long reply, but you peaked my interest and that is what this site is all about. I also like the fact that you are taking some unconventional approaches to figure things out. New ideas we can all kick around only serves to further our knowledge. If your intent is to identify the die and not associated VAMs then you might have something that contributes to our knowledge, but it might not result in a die variety in the VAM world. To the best of my knowledge in 1881 the 18 was added at the master die stage, and the 81 to the working die. This is why the first two digits always line up. I got into this pretty deep on the above page. But the date punches used were visibly different in some areas, so we know the same punches were not available in both places. Otherwise the 1s and 8s would have the same characteristics, and they definitely vary. Being a palindrome you would have only needed 2 punches. There is a lot of other evidence on this introduction of the date into the working dies, but I will let you read it on the above page. For the 1881-O there are no definitive near/far date issues to my knowledge. Proper measurement of this anomaly (as defined by Roger Burdette who I think is the authority) starts with the distance from the neck to the first 1 and not alignment to a denticle as is often described. This leads to the understanding that for all dates beginning with 18 (most Morgans) the way the date placement was devised (my opinion) was that the 18 was pretty much fixed in location using a jig at the master die stage. But the first digit and the last digit in the date always had to line up vertically. So it was the third digit, in this case the second 8, that had to move around to have an evenly spaced date. The last digit is the key because they varied in width slightly (1, 2, 3, 4, etc.) with the passing years. Since there are no major near/far or high/low date issues identified (probably other jigs prevented this) I believe the alignment issue you saw is as Messydesk described and just not significant enough to be recognized. Remember the stars were added by hand because the reduction lathe was not used to create them. This was not because it could not do it, but because the Mint personnel lacked the skill/training to use it this way. http://www.1881o.com/reduction.html Any movement or slight rotation of a star punch would give you a different result. On the two examples you pulled there is another factor that I would have to consider. The toned coin has been repolished several times or the working die was not completely imprinted from the working hub. I know this because of the hair curl above the date. If you look at them they are different. On the toned coin they are incomplete and if this came from the creation of the die then that can change things. All of that said, I think there is a way to figure out the master dies, which I think might be more interesting. I have not had a chance to analyze it yet, but I will get there. If you can link the working dies to the master dies I think you have a better working knowledge to figure out the working dies. But all that is something I need to work on. If you have not read "From Mine to Mint" by Roger Burdette I would recommend you get a copy. There is more information on the die creation process there than any other source I have located. Keep studying and communicating please because fresh thinking helps us all.
Yes rotation of the star punch would provide me with a different result. But that really is the whole point. The rotation of the stars may deviate from working die to working die but that rotation is a permanent characteristic of a working die.
True, but maybe you just need a lot more data to prove the point. I would keep digging and draw some conclusions. Good luck and thanks for sharing. If you have not read From Mine to Mint it really is essential to understanding all the minting steps and it is the top of my recommendation list.
I want to emphasize what I posted in this thread earlier - "Gives me indication it may be possible to identify all 1881-O obverses by mapping these six design features for each die." I have not done much analysis on Morgans and do not know the extent of deviation of the 6 targeted design features from working die to working die. It does appear the deviation in placement of the mint mark on the reverse is fairly static. Something I wasn't expecting. It is not as randomly placed like you see in other coin designs such as the Lincoln Cent.
The mint mark really can move around. Just on the 81-O it can be centered, set left, set right, tilted left, tilted right, doubled in about half a dozen ways, overstruck, and high.
On Morgan dollars, the stars were part of the master hub, so there is no variation from die to die within any year except 1878, while the designs were being fine-tuned, and no variation from 1879 to 1904.
Interesting since I thought I had a conversation with Accurateye where he was saying that only the Liberty device was transferred to the master hub and it was not until after 1900 that anything else was attempted. I remember the conversation as all other features being introduced to the master die through punches. I need to look back through my notes but certainly your knowledge is deeper than mine.
And Roger has more complete info than I do. I'll amend my assertion to say that the stars were part of the master die. The question is then how many years a Morgan dollar master die lasted. It could have been several or even tens of years, for all I know. If I look at the Indian cent obverse, it remained unchanged from 1865 to 1886, then the legend was moved. Master die change? Perhaps.
Do we have an idea how many working dies an average working hub could create? That would be a good clue as to how many hubs a master die could impress. According to Wexler, 1886-ish was when IHC lettering was transferred to the galvano; prior to this, the peripheral letters were part of a single punch. Don't know how this relates to Morgan production, aside the inference that the larger sizes of the features involved would lend themselves to easier implementation of new processes than the smaller Cents. And rotation of the stars would imply a similar rotation of the rest of the lettering relative to the central device, confirmation of which would help inform knowledge of the creation process. With all that said, I'm unsure how the introduction of CAD tracing into a research process perfectly attainable via purely optical/imaging methods could be anything but an additional opportunity for error.
I saw an estimate of the hub to die ratio at some point but I would really have to dig to find it. I would not have to be too many because the working dies were not in the thousands, but in the hundreds. For example, in 1881 the New Orleans Mint received 119 working dies. I have not found a reference for the split between obverse and reverse but would imagine the number to be about even. In all my research I discover that there are some significant roadblocks, as there would be today. Many of the things we show some curiosity about were just part of the minting process and I am sure they had no realization that anyone would care. So production information on many details died with the workmen. I would think the best option for much of this would be someone who performs similar work at the Mint today. The second chapter John Mercanti's new book on the ASE series goes into a lot of detail on production and it might be a good source for that question.
By the way, I think I remember that the use of the Hill Reduction Lathe became a battle between the Barbers who held the power and agents of change in the government (imagine that). The restriction of the use to just the two primary devices may have been their resistance to change. Also the Hill Reduction Lathe was invented in England and brought here, but with some modifications we have not been able to trace down. I believe it was treadle powered and the effort to do a reduction accurately was somewhat dependent on just the skill of the operator. It was apparently a real improvement over its predecessor, but much lower technology than its successor, the Janvier. The Janvier is often shown in pictures of all coin reductions, but it did not come into use until later and it was steam powered in the beginning. An interesting side note is that the manufacturer of the Janvier put themselves out of business. The reduction lathe was so good that it could not be improved upon until electronics came onto the scene. With few Mints and a great product there was no new demand.
