Grading is BS

Discussion in 'Coin Chat' started by davidh, Jan 14, 2017.

  1. Insider

    Insider Talent on loan from...

    Don't see the scratch, only some tiny gouges. Anyway, IMO the coin is XF.


    ]
    I say some folks should not crack out coins that are graded in slabs.

    Impaired Proof.

    Finally, Pick up a raw coin and grade it. How long did it take you. Your speed and accuracy will improve with the experience that comes with practice. A minute a coin IS A LIFETIME! It is also a MYTH. :happy:
     
    Last edited: Jan 16, 2017
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  3. V. Kurt Bellman

    V. Kurt Bellman Yes, I'm blunt! Get over your "feeeeelings".

    Earlier, but not Barbers per se. I've never owned a Barber I thought needed dipping. I have one Barber dime I'm still thinking about dipping, but I haven't pulled the trigger.
     
  4. V. Kurt Bellman

    V. Kurt Bellman Yes, I'm blunt! Get over your "feeeeelings".

    You're right. Senility rears its ugly head. It's S-10.
    I down-batched it thusly:
    12 oz. water
    35g Thiourea
    35g Citric Acid
    Fill to 16oz. with water

    Be prepared: this is a VERY SLOW ACTING dip compared to EZest. You can retain just the "right" amount of toning by pulling the coin.
     
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  5. V. Kurt Bellman

    V. Kurt Bellman Yes, I'm blunt! Get over your "feeeeelings".

    Ron Guth said it in the video at the top of the thread. Toward the end.
     
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  6. Gilbert

    Gilbert Part time collector Supporter

    In reading your ingredient list, Kurt, where does the S-10 come in?
     
  7. V. Kurt Bellman

    V. Kurt Bellman Yes, I'm blunt! Get over your "feeeeelings".

    It's a formula published by Eastman Kodak back in the 1960's. They never made it as a commercial product, but only published a formula. Their batch size was a gallon. It was used to remove silver sulfide stains from textiles used in B&W photography darkrooms. Things like towels, aprons, your best linen shirt, etc.
     
  8. Gilbert

    Gilbert Part time collector Supporter

    When you say "very slow acting" does that mean submerge a coin in the solution and check back in a day? Hour? Week?
     
  9. -jeffB

    -jeffB Greshams LEO Supporter

    Looks like it might be time to order in some thiourea. Do you see any problems with downsizing this 5-10x for a first experiment? (I've got a good scale and volumetric equipment.)
     
  10. Gilbert

    Gilbert Part time collector Supporter

    Would I be correct in assuming that the Thiourea and Citric Acid are in powder form?
     
  11. davidh

    davidh soloist gnomic

    See 32:21 in the video.
     
  12. Insider

    Insider Talent on loan from...

    :rolleyes: :hilarious::hilarious::hilarious: I think TPGS folks like David Hall and Mark Salzberg (or other long-time finalizers) might disagree with the percentage given in the video. IMHO, 80% seems a little low. Furthermore, I'll bet at least 40% of the MAJOR MARKET MAKERS would "ace" the test in the video. The rest would beat 80%...but we'll never know. :D
     
  13. V. Kurt Bellman

    V. Kurt Bellman Yes, I'm blunt! Get over your "feeeeelings".

    Correct. A partial dip might take 45 seconds. To blast white, maybe 2 minutes.

    NEVER dip circulated coins. It creates an odd look. The whole point of dipping is to re-reveal toned over luster.

    The citric acid can be found in the canning supplies section of a good grocery store. Thiourea can be the cheapest grade from a chemical supplier.
     
    Last edited: Jan 16, 2017
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  14. dd27

    dd27 New Member

    Thank you both for the info! :)

    Naturally, I am now wondering how they arrived at this 80% accuracy figure. If anyone knows, please share. In the meantime, I will see if I can find any info about that accuracy rate on the PCGS website and I'll email them if not.

    ~ Mark
     
  15. -jeffB

    -jeffB Greshams LEO Supporter

    I'll revisit this later. I've got a Barber half in AU details and a 17-P T1 SLQ MS details that are toned with psychedelic splots on the reverse due to time in a "Twentieth Century Type Coins" display, possibly in a smoking household. The SLQ might sell as-is, but I think I'll need to do something with the half. Both have an obverse cleaning, although it's not catastrophic.

    I'll start a separate thread (or two) when the time comes.
     
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  16. dd27

    dd27 New Member

    I searched the PCGS website regarding Ron Guth's 80% accuracy figure, but I did not find anything. I used both the PCGS internal search function, and using:

    site:http://www.pcgs.com "80% accurate"
    site:http://www.pcgs.com accurate
    site:http://www.pcgs.com accuracy​

    I submitted a question to PCGS asking if "80% accuracy" is based on a formal inter-rater reliability study or not.

    The exact quote from the video is:

    ..."and even then there are differences in grading. What we've learned is that the best graders get it right about 80% of the time. But when you go from grader to grader to grader, statistically they all sort of even out." - former PCGS President Ron Guth

    CoinWeek: We Take the PCGS Grading Challenge!

    ---

    The PCGS grading process is explained in this 2007 video on YouTube: PCGS Grading Process Video

    And this quote is from the PCGS website, on the FAQ page:

    "Every coin submitted to PCGS for grading is reviewed by a minimum of two and in most instances three or more of our grading experts." - PCGS.com/FAQ/Miscellaneous/How many PCGS experts (graders) review my submission?
     
    Last edited: Jan 16, 2017
  17. Silverhouse

    Silverhouse Well-Known Member

    We shall see. As I said if PCGS allows room for gouges on coins, then perhaps a few hairlines on a 122 year old coin won't matter. At any rate I love the coin.
     
  18. GDJMSP

    GDJMSP Numismatist Moderator

    I've tried to stay out of this, I really have. But I just -can't - help - myself !! :(

    Well, I suppose the answer to that question depends on who you ask, as well as when you ask them. For example, there was a time when I used to say that NGC and PCGS graders had assigned the "right" grade about 85% of the time. But that was long ago.

    In today's world, I say something that's just slightly different. Today I would say that they over-grade coins about 90% of the time ! And sometimes grossly over-grade them !!
     
  19. V. Kurt Bellman

    V. Kurt Bellman Yes, I'm blunt! Get over your "feeeeelings".

    Yet they still are the industry standard, not the old school technical grading we learned. The hobby has moved on, Doug, from what we originally learned, ESPECIALLY in the mid-50's to low-60's grade range. Yesterday's 58 is today's 62, if the coin is pretty.

    Today's MS60 is a truly ugly beast.
     
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  20. green18

    green18 Unknown member Sweet on Commemorative Coins Supporter

    You said it Brother.......give a nice, comely '58. :)
     
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  21. dd27

    dd27 New Member

    And then there is today's shot across the bow by NGC, discussed on the forum here:

    Holy .... NGC just took PCGS behind the woodshed! ... and here:

    Let's get ready to rumble... NGC vs PCGS

    regarding:

    Salzberg Advises: Research PCGS Populations and Prices

    Here's a quote from the first part of Mark Salzberg's article/editorial:

    "In November I announced that PCGS-certified coins would no longer be eligible for inclusion in the popular NGC Registry. I received many positive comments from those who have closely followed graded coin populations and prices. Others asked me, “Why? What is the difference between NGC and PCGS?”

    Let me show you.

    Over the last five years or so, I have noticed a perplexing trend at PCGS. There has been a dramatic increase in the grades assigned by PCGS for a wide range of coin types and, consequently, I believe that this has caused an extraordinary reduction in the value of many PCGS-certified coins.

    As an NGC grading finalizer for the last 30 years, I have worked to ensure the accuracy and consistency of NGC’s grading. I have also closely observed the grading standards employed by our competitor and I can say with confidence that I believe that the grading standards PCGS uses today are completely different from the standards it used 10, 20 or 30 years ago.

    It is my belief that the sudden change in PCGS grading standards around five years ago is harmful not just to collectors of PCGS-certified coins, but to the entire hobby." {continued on NGC website...}​
     
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