How Worn Can A Die Be and Still Strike MS Coins?

Discussion in 'Coin Chat' started by Hommer, Sep 19, 2017.

Page 3 of 7
  1. rmpsrpms

    rmpsrpms Lincoln Maniac

    I said nothing of the sort. What I did say is that the discussions that dispute my understanding were wrong.

    I agree, but I was simply responding in kind. May I direct you to Doug's first reply to my post:

    "Completely untrue. An idea that has been discussed at length many times and proven to be false."

    But again, please provide those discussions, or any reference of any kind, that proves me false.

    In the end of this discussion, I will either concede to being wrong, having been shown that the TPGs and majority of numismatists agree with Doug's viewpoint, or I hope that you and Doug will concede to being wrong.

    By the way, I still do think this is relevant to the OP's question, but if he believes otherwise and would prefer this discussion to move elsewhere, I'd be happy to start it up as a separate thread.
     
    rmpsrpms, Sep 20, 2017
    #41 + Quote Reply
  2. Avatar

    Guest User Guest



    to hide this ad.
  3. mikenoodle

    mikenoodle The Village Idiot Supporter

    Here's the logic:

    A=B. C is not A, but can still be = B.

    My claim is that what Doug said is widely accepted, that doesn't mean what you said is wrong.

    Those are my words
     
    mikenoodle, Sep 20, 2017
    #42 + Quote Reply
  4. baseball21

    baseball21 Well-Known Member

    Those have been around for decades according to other threads from people that have bought and sold them before. Also of course they end up with an error specialist that makes perfect sense
     
    baseball21, Sep 20, 2017
    #43 + Quote Reply
  5. rmpsrpms

    rmpsrpms Lincoln Maniac

    Here's an animated example of a lustrous coin based on my definition of luster. Note the coin is a business strike, with no mirrors, and is MDS. By my understanding of Doug's definition, this coin is not lustrous.

    [​IMG]
     
    rmpsrpms, Sep 20, 2017
    #44 + Quote Reply
  6. mikenoodle

    mikenoodle The Village Idiot Supporter

    I agree that it is relevant but also think that my example of the 1922 No-D better illustrated an answer to the OP's question without muddying the waters with all of this discussion about luster and reflectivity.

    I think you both got a bit into the weeds with this tangential argument while I illustrated clearly how a worn die could produce Mint State coins.
     
    mikenoodle, Sep 20, 2017
    #45 + Quote Reply
  7. rmpsrpms

    rmpsrpms Lincoln Maniac

    I think the OP's question has been answered. A worn die of course produces Mint State coins. How could it be otherwise?

    The luster discussion is for sure tangential. My original point was that very worn dies actually still produce strongly lustrous coins, though the distortion of the devices (causing "mushy" features) can degrade from eye appeal and reduce the grade. The coins will still be MS, but common coins in VLDS can't really grade in the upper echelons.

    The 22 no-D is a special case, in that the distortions are so severe as to make it into a defacto error coin of particular rarity.
     
    rmpsrpms, Sep 21, 2017
    #46 + Quote Reply
  8. GDJMSP

    GDJMSP Numismatist Moderator

    If that's what you think then you don't understand my comments at all. I would readily agree that coin is lustrous.

    I have never claimed that MDS or LDS coins do not have luster - of course they can have luster. My claim is quite simple, when all other things are equal, an EDS coin will have a higher quality of luster than coins struck with the same dies in MDS or LDS.

    I also said that all struck coins (when they leave the dies) have luster, including Proofs, it's just a different kind of luster. And that there are many different kinds of luster.

    For example, compare a Morgan and a Peace dollar, both coins absolutely have luster. But yet they look as different as night and day from each other. Frankies and Walkers both absolutely have luster, but yet they are quite different from each other, as are all other halves. The same thing is true with all gold coins, all copper coins, all silver coins. Each one has its own unique kind of luster.

    The luster we see on coins, all struck coins, is nothing more than a function of reflection and refraction. That is cold hard fact, not opinion.

    You say the Proofs don't have luster, take a Proof coin and make an animated pic under the light just like you did for that cent. You'll see that the reflection of light rolls around coin just like it does on that cent. That's luster ! Will it look different than it does on the cent ? Of course it will, because it is a different kind of luster ! But that does not mean that there is no luster.
     
    GDJMSP, Sep 21, 2017
    #47 + Quote Reply
  9. GDJMSP

    GDJMSP Numismatist Moderator

    If you want to see high magnification pics of different kinds of luster read this thread - https://www.cointalk.com/threads/morgan-toning-vs-peace-toning.12578/

    Then look at this link - http://photobucket.com/gallery/user/USS656/media/cGF0aDovMTk2NEtlbm5lZHlQcm9vZkxlZnRvZkkuanBn/?ref=

    I first used the same illustration I used in that thread - /\/\/\/\/\ - over 20 years ago to try and explain luster. I'd never seen anybody else use that simple illustration before, never even heard of it before that. But today they use that same illustration in the ANA classes to explain and illustrate luster. Did they get the idea from me ? I have no idea, it's certainly possible that somebody else had the same idea I did. As a matter of fact it seems they use the same illustration in scientific circles -
    http://lab-training.com/2014/05/06/dispersion-of-light-in-spectroscopy/

    In both cases, my illustration and the one found in that link, show how light is reflected and refracted from the fine grooves of flow lines on a coin. Change the angles slightly, change the height, and or width, and or depth of the grooves and you change the luster.

    On business strikes the flow lines are higher, wider, and deeper than those on Proof coins. But the flow lines are still there on both coins, they merely reflect and refract the light differently.
     
    GDJMSP, Sep 21, 2017
    #48 + Quote Reply
  10. rmpsrpms

    rmpsrpms Lincoln Maniac

    Hmm, I agree with a lot of what you said. I think we're getting somewhere! I don't see much point in arguing about proofs vs business strikes, but I do think it will be instructive to look at VEDS vs EDS vs MDS vs LDS. I might have a progression available to show that, I'll need to dig something up and snap some shots. Note that even in EDS the flow lines start to produce luster, so you really must go back to VEDS to see the flat nature of the resulting coin. Another possibility is a die that received a bad clash and had the surface ground and polished such that the flow lines were removed, resetting the process.

    Just for fun, here's a pic I took of a 1994 IIBIE showing the flow lines worn into the die. We know the die struck a lot of coins by this time, given the die breaks, and the flow lines show this wear as well:

    [​IMG]
     
    rmpsrpms, Sep 21, 2017
    #49 + Quote Reply
  11. GDJMSP

    GDJMSP Numismatist Moderator

    The link for the pictures is Photobucket, and it can be somewhat problematic at times. So if you can't get the pics to open, I'll post them here for you. The pics were taken at 90x. And it is a mix of both Proofs and business strikes. And the flow lines are plain to see on both.

    1923PeaceLeftofR.jpg 1924PeaceRightofR.jpg 1942LibertyHalfRightofY.jpg 1960FranklinProofLeftofE.jpg 1964KennedyProofLeftofI.jpg


    By the way, the pics were taken by Darryl, USS656
     
    GDJMSP, Sep 21, 2017
    #50 + Quote Reply
  12. GDJMSP

    GDJMSP Numismatist Moderator

    I certainly hope so because I've been saying the same thing all along.
     
    GDJMSP, Sep 21, 2017
    #51 + Quote Reply
  13. rmpsrpms

    rmpsrpms Lincoln Maniac

    Well, not exactly. You jumped off the deep end with your mirror comments:

    "The quality of the image you see in the mirror is due to the high quality of luster of the silver backing on the mirror"

    It was this comment that made me think you were trolling me. Hopefully you'll realize your mistake there and retract. The "luster" of a mirror has nothing to do with numismatic luster. Mirrors are certainly "lustrous", but not due to the flow lines that I think we are in agreement are the cause of numismatic luster.
     
    rmpsrpms, Sep 21, 2017
    #52 + Quote Reply
  14. GDJMSP

    GDJMSP Numismatist Moderator

    On the contrary, they are exactly the same thing. The silver backing on a mirror has flow lines just like a business strike coin or a Proof coin has flow lines. Granted, the flow lines on the mirror are not created in the same way as those on coins, but they are most definitely there. They are just very, very fine, just like those on a Proof coin, so you can only see them with high magnification.
     
    GDJMSP, Sep 21, 2017
    #53 + Quote Reply
  15. rmpsrpms

    rmpsrpms Lincoln Maniac

    Sorry, but there are no flow lines on a mirror. There is microscopic grain structure, but not flow lines. There are polish marks on the glass, but not flow lines. Mirrors are made by depositing Aluminum on polished glass by vapor deposition.
     
    rmpsrpms, Sep 21, 2017
    #54 + Quote Reply
  16. GDJMSP

    GDJMSP Numismatist Moderator

    Depends on the mirror, some are, some are not. You can even make a high quality mirror right at home.

    But even with vapor deposition the metal material goes from a condensed phase to a vapor phase and back to a condensed phase. As such, when it is deposited on the glass the metal flows, and when metal flows it creates flow lines.

    The flowing of the metal in other methods of making mirrors also occurs.
     
    GDJMSP, Sep 21, 2017
    #55 + Quote Reply
  17. rmpsrpms

    rmpsrpms Lincoln Maniac

    Wow, the lengths you will go to not admit you are wrong are impressive.
     
    rmpsrpms, Sep 21, 2017
    #56 + Quote Reply
  18. Oldhoopster

    Oldhoopster Member of the ANA since 1982

    Metal doesn't flow during the vapor phase deposition process. Now if you want to debate whether the deposited material forms crystalline domains and multiple orientations may result in light scattering along grain boundaries, then you might have something (personally, I don't think so, but I haven't bothered to check the literature to see if they have an effect)
     
    Oldhoopster, Sep 21, 2017
    #57 + Quote Reply
  19. rmpsrpms

    rmpsrpms Lincoln Maniac

    The deposition is fairly slow, so the grain structure is very fine. Too fast, and larger grains form, which compromises the reflectivity.
     
    rmpsrpms, Sep 21, 2017
    #58 + Quote Reply
  20. Oldhoopster

    Oldhoopster Member of the ANA since 1982

    So how about this. Lots of grain boundaries could increase the potential for light scattering. And the scattered light could be thought of as luster. So therefore, mirrors have luster, Doug was right even though he wasn't, and the coin talk community can move On to the other stimulating discussion topics :dead:

    I'm going to Lowe's and buy the best looking mirror I can find. Then send to to PCGS to see if I can get it in a MS-69 DMPL holdero_O

    Time for a beer
     
    Oldhoopster, Sep 21, 2017
    #59 + Quote Reply
    mikenoodle likes this.
  21. rmpsrpms

    rmpsrpms Lincoln Maniac

    I'm good with that, and I'll join you for that beer!
     
    rmpsrpms, Sep 21, 2017
    #60 + Quote Reply
72 more messages...
Page 3 of 7
Draft saved Draft deleted

Share This Page