Capped Bust half dime attribution tool

Discussion in 'US Coins Forum' started by bikergeek, Nov 23, 2025.

  1. bikergeek

    bikergeek Well-Known Member

    Greetings. Just wanted to share this tool for those who are interested in trying to attribute Capped Bust half dimes: https://groovycoins.com/attribution

    Feedback / comments requested!
     
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  3. Mr.Q

    Mr.Q Well-Known Member

    Thank you.
     
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  4. SensibleSal66

    SensibleSal66 U.S Casual Collector / Error Collector

    Nice site!! Now I just need to find a Half Dime. :D
     
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  5. justafarmer

    justafarmer Senior Member

    Not familiar with Capped Bust Half Dimes but

    My count shows the series used 39 different Obverse Dies and 36 different Reverse Dies?

    What about reverse I, O and II ?

    Nice Site - is this your creation?
     
  6. Publius2

    Publius2 Well-Known Member

    I had the privilege of hearing @bikergeek talk about and demonstrate this site at last week's JRCS Zoom meeting. He developed it from previous work and used AI to write the software. It is the most complete and accurate capped bust half dime work out there and incorporates the latest research and scholarship (his and others) since Logan and McCloskey published their work in 1988.

    The site is interactive, i.e. it responds to the selections you make on the coin's characteristics to narrow the possible dies and die marriages. It also has a gallery of hi-res photos of all the die marriages and remarriages and maps out the emission sequence.

    The site works on my PC laptop (Dell) and also on my Android phone (Samsung). Although it's a little difficult on the phone due to the small screen size. Nevertheless, I will probably find it a useful adjunct to the book while on the bourse floor. I have a small, cheap pad that I bought from a waitress who was down on her luck, even though I didn't need it, so I'll try to see if the site will work on that. I'm sure it will work on bigger and better pads.

    I have used this interactive site to attribute about a dozen coins since last week and found it generally easy to use. For someone accustomed to attributing from the book, it took a bit to acclimate to a different methodology. And of course, specialty collectors like myself develop their own set of favored characteristics to identify die marriages and that will necessarily differ slightly from those chosen by the author.

    But that's a nit. This site is very neat. And I've already given the author a couple of suggestions to make it better, in my humble opinion - he may disagree.

    So, kudos to @bikergeek for developing this and particularly so for making it available at no cost to the collecting community. I predict his name will go down alongside Bill Bugert not only for scholarship but for making his massive work on the Liberty Seated Half Dollars available gratis.
     
  7. bikergeek

    bikergeek Well-Known Member

    @Publius, thanks very much for the very kind words! I've got your note on attributing the 1835's handy. I'll get back around to that when I take another swing thru the detailed attributes. Today I had a bug to fix, and also an improvement on the Set List page: https://groovycoins.com/lm-xref (where I found myself clicking on the images, and being mad that they didn't go fullsize like the gallery page images do).
     
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  8. justafarmer

    justafarmer Senior Member

    Just so I get a basic understanding of how the variety cataloging system for Capped Bust Dimes works - looking @ 1829 for instance, I see a listing for LM-6.1, LM-6.2, LM-6.3 and also listings for LM-7.1, LM-7.2, LM-7.3.

    Are each of these a listing for a new unique different die pairing or an indication of a different die stage for each of the two (6 and 7) die pairings?
     
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  9. Publius2

    Publius2 Well-Known Member

    The early half dimes, 1794-1837, are a bit unique in that there are a lot of remarriages. To explain, a die marriage is the uniting of a unique obverse and reverse die to create a coin. The coin you mention, the 1829 LM-6 is the pairing of Obverse Die 4 and Reverse Die E. The first time those two dies are used together to strike coins dated 1829 is known as the LM-6.1. If the next use of the reverse die is with a different obverse die, then a different die marriage is created. But if that reverse die is then brought back together with Obverse Die 4, the resulting coins struck are known as the second remarriage, the LM-6.2.

    Note that remarriages are defined by the REVERSE die. That is because the reverse dies were often used across multiple years resulting in die remarriages that spanned two or even more coinage years.
     
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  10. micbraun

    micbraun coindiccted Supporter

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  11. justafarmer

    justafarmer Senior Member

    Thanks for the info. I believe I now understand the basic LM variety cataloging system.
     
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  12. Mr.Q

    Mr.Q Well-Known Member

    @Publius2 I also would like to thank you for the info., very interesting. Happy and safe holidays to you and yours.
     
  13. Publius2

    Publius2 Well-Known Member

    Nailed it in one!
     
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  14. CoinCorgi

    CoinCorgi Tell your dog I said hi!

    Very nice site...works well seemingly in Firefox...

    Curious what someone else gets...

    Capped Bust Half Dime 1833 Obv.jpg

    Capped Bust Half Dime 1833 Rev.jpg
     
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  15. bikergeek

    bikergeek Well-Known Member

    @CoinCorgi I will let others answer your attribution challenge - but I will say, that coin is near and dear to my heart because, for a while there earlier this year, I thought it might need to be split into remarriages and I studied it pretty hard.

    @Publius is a source of knowledge on this (and other) series and he and I chat frequently. But one thing I'd like to append to his comment, "remarriages are defined by the REVERSE die," is: "so far." I am of the opinion that we will find remarriages based on "unfaithful" obverses too someday.

    A hypothetical example (this is not a real thing, I must stress!). On this page you can see my chart of 1833 Obverse 3 (the one used by CoinCorgi's image above, with the 8 and 3 close at the top): https://groovycoins.com/obverse-die.jsp?year=1833&die=3

    Important: on my model, the bold text is stuff that MUST BE on the coin, and the normal font text is stuff that MAY BE on the coin.

    1833 Obv 3 currently doesn't show any remarriages that are owing to the obverse. The progression from its early use in LM-7, to LM-8, and ending in LM-10 is progressive.

    But: what if you found an LM-8 (meaning a coin that paired 1833 Obverse 3 with Reverse X) that didn't have the "mandatory" die crack rim to cap thru B...? Then there'd be examples of LM-7 without the crack (since it may happen in LM-7 but isn't mandatory), and of LM-7 with the crack... and examples of LM-8 both with and without. That would change the simple 3-box flow below to something more complicated that might have: LM-7.1 (no crack), LM-8.1 (no crack), LM-7.2 (yes crack), LM-8.2 (yes crack).

    Or more simply (and more likely) would be: LM-8.1 (no crack), LM-7 (crack absent at first but develops), LM-8.2 (must have crack).

    I'd then lock myself in a room with a case of Mountain Dew and a supply of bean burritos and try to decide when that crack spreads from the ear "across cheek to neck". Lol. Anyway, just a hypothetical.
    upload_2025-11-26_23-55-1.png
     
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  16. bikergeek

    bikergeek Well-Known Member

    Ah, and to @justafarmer, @Publius2 's explanation seems to have filled the bill nicely. But if you want to see the picture for the 1829s and how they used Reverse E (which is the reverse for both 1829 LM-6.x and 1829 LM-7.x), the model shows how this reverse die was "unfaithful" to its original obverses. https://groovycoins.com/reverse-die.jsp?die=E
    upload_2025-11-27_0-13-1.png
     
  17. CoinCorgi

    CoinCorgi Tell your dog I said hi!

    Love it!
     
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  18. justafarmer

    justafarmer Senior Member

    Looks to Me Reverse-M suffered from acute wanderlust - my count comes up with 8 different die pairings stretching over a period of 4 years of coin production. Still wonder what happened to Reverse-I and II.
     
  19. justafarmer

    justafarmer Senior Member

    My counting shows there to be 93 different die marriages for the Capped Bust Half Dime coin series. Add the recognized re-marriages for a total of 123 listed varieties.

    Below is a table I created showing the 93 different Marriages/pairings listing their respective obverse and reverse sorted in ascending order by their LM#, then by Obverse Die and again by Reverse Die.

    Corrected Capped Bust Half Dime Die Pairing List.jpg
     
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