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The mathematics of coin grading
logger7
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PCGS has the numbers on their statistics page: https://www.pcgs.com/statistics
Nearly 265K coins graded in the last month. How would you figure the breakdown of actual coin grading? My guess is 4 coins a minute per grader, which works out to 240 coins an hour or 1920 coins graded in an 8 hour day. Presumably you have two or three graders look at each of these coins as well as a finalizer. How many graders are currently working full time? How many workers do you have to have to handle the slabbing, the gaskets, the machines, etc.? Are the correct gaskets for each coin all ready for the slabbers with all the other slab materials, assembly line style?
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I cannot envision an individual places each coin inside a gasket, places that in half a shell, places the front/back inserts, places the other half shell and seals it.
There has got to be some type of automation which must be super high text to not damage coins.
"Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety," --- Benjamin Franklin
4 coins a minute per grader sounds generous. At one point I heard they were given just 8 seconds per coin.
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I’m guessing the “8 seconds per coin” wasn’t from an extremely reliable source, who would know. I don’t believe it.
Mark Feld* of Heritage Auctions*Unless otherwise noted, my posts here represent my personal opinions.
If at least the 4 coins a minute is accurate, that would mean the grader has the coins for 15 seconds. If that 8 seconds to examine the coin is right, that leaves 7 seconds (3.5 seconds each way) for the grader to pick up or pass off the coin.
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Speaking on vintage US (non modern) - Graders aren’t forced to grade any amount in particular. You take as much time as you need. Sustaining a rate of 15 seconds a coin for 8 hours straight isn’t realistic. Sure, there are orders where you grade at 15 seconds per coin, but there’s also orders where you grade at 2 minutes a coin. I’d say most professional graders doing non-bulk orders grade around 100 coins per hour when focused. The slower guys grade a bit slower, and the faster guys grade a bit faster.
My source is my time as a PCGS grader
Head coin nerd @ Rarity7
.
Mark, I know you used to be a grader.
How many coins did you usually grade in an hour? A reasonable estimate of your recollection would be fine.
Also, did the amount of time change (and what type of differences could be expected?) if you were grading what would now be ~$200. widgets, ~$4,000. early federal's or ~$80,000. super coins?
I mean if we're doing the "mathematics" we should probably have some reasonably accurate numbers to base our hypotheses on.
“We are only their care-takers,” he posed, “if we take good care of them, then centuries from now they may still be here … ”
Todd - BHNC #242
Thanks for the real world corporate grading experience. Aren't there metrics for "accuracy" in grading in line what their best, more seasoned graders do? Though there may not be any hard and fast rules on how much time you were given for grading I'd think that there would be an expectation of certain time frames. Ideally they'd want coins graded as quickly and accurately as possible. Do they have a different group of graders on walkthrough and express submissions?
You're back and posting again! I know what this means...
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As much as I love coins, I would go out of my mind spending an eight hour day having to grade coins at such a high speed. That explains why there are such inconsistencies as to the grades that colonials receive. It’s difficult enough to accurately grade one at a normal pace.
I've always been curious if bargain basement economy submissions receive on average less time per grader per coin than say walk-throughs.
If you grade 100 coins per hour, each grader grades 200,000 coins per year. 265k coins per month is 3,180,000 in a year. If each coin is seen by a 4 person grading team, that's 12,720,000 grading events per year. That's 64 graders required.
All comments reflect the opinion of the author, even when irrefutably accurate.
I could probably believe that JA could look at one of my coins in 8 seconds and grade it better than me, noting PVC and other things that I missed, but that's about it. :'(
Whatever the time/coin, however many “co-workers” in the building and whatever the pay it isn’t a job I would ever want to do.
All I hear in my head after reading this thread is the crack of the whip.
"Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety," --- Benjamin Franklin
I’m not buying that (including the “they were given” part) either. And I still doubt that what you heard was from an extremely reliable source. But if he was a professional grader, please convey my apology to him.😉
Mark Feld* of Heritage Auctions*Unless otherwise noted, my posts here represent my personal opinions.
Overall, my recollection is that my experience was quite similar to what @OwenSeymour posted about his.
We weren’t given any time limits. As far as the amount of time changing based on the types and value of coins - not surprisingly, for a number of reasons, some coins are more difficult to assess and grade than others. And that’s not based on the value of the coins. i wanted to get the grade of each coin “right”, whether it was a seven figure one or a $50 one.
I “graded” fewer coins than my fellow graders, as one of my other responsibilities was quality control, which took up a good part of my days. By that, I mean that after the coins were encapsulated, they were brought back into the grading room for examination. I typically reviewed most of them (while other graders reviewed smaller quantities and finalizers viewed all of the higher tier orders) looking for any that might appear over-graded or under-graded. If I thought that a grade change should be considered, I placed a sticker on the holder and those
coins were shown to a finalizer for his decision. It wasn’t uncommon for us to have discussions (and occasional arguments) about what the grade should be.
In addition to looking at each coin in the holder, I checked the information on each grading label to be sure it was accurate and also made sure that the holders were actually sealed.
Back then - in the 1990’s - if I’m remembering right, I think our small team of graders graded about 2000 coins a day. Things have changed a little bit since then.😉
Mark Feld* of Heritage Auctions*Unless otherwise noted, my posts here represent my personal opinions.
Thanks Mark @MFeld (and good morning!), even if you really didn't answer quantity per hour!
I saw the @OwenSeymour post after I wrote and posted mine (I was asking you and he was answering my thoughts at the same time!
), but between the two of you, that seems to confirm some things I have heard elsewhere.
His post said 100 coins an hour when they were "doing non-bulk orders" AND "when focused" (my emphasis on both). That also suggests there are other duties involved (like the quality control like you mentioned) that aren't fully engaged in grading duties, and leaves some movement in speed and scale.
This also makes sense to my mind. I recently looked a couple hundred CBH's, checking and writing cryptic (quick) notes for a friend similar to grading, kind of ... coins were already graded however. It was a little tedious and I wasn't getting paid (lunch and a ride to the airport after he put me up for the weekend
), but I probably did about 50 an hour that day (when I was focused), and I'm no pro', nor was I in a streamlined situation, or working with raw coins, feeling like I had to earn my value, etc.
FWIW, no way would I want to do that as a pro' 8 hours a day, 4 or 5 days a week, 45 to 50 weeks a year ... but I sure appreciate those who can do it, and especially those who do it well.
“We are only their care-takers,” he posed, “if we take good care of them, then centuries from now they may still be here … ”
Todd - BHNC #242
Mr. @pursuitofliberty, I didn’t really answer your question of how many coins an hour I graded, due to the quality control work I did, which slowed me down on my grading. But, in general, as mentioned, my experience was similar to that of @OwenSeymour.
By the way, I left NGC before grading of moderns started. Thank goodness!😉
Mark Feld* of Heritage Auctions*Unless otherwise noted, my posts here represent my personal opinions.
If the majority of recent PCGS slabbing is moderns, only take a few seconds to determine 68 - 70 grading. And if grading a recent Mint release, low probability of counterfeiting.
I had heard somewhere that usually a coin was only looked at by two graders. If they agreed, it was good to go. In case of a difference between the two it made it to a third (maybe the finalizer?) to decide, or take further review if necessary.
265K coins in a month, but probably at least 90% of that is bullion and moderns. And bullion and moderns can be graded VERY quickly.
Doggedly collecting coins of the Central American Republic.
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Im guessing coins that have some circulation take the longest. XF-AU or maybe an MS61.
After a while I'm sure that determining a 62-66 coin becomes second nature so those would move along well.
Im my mind I'm always thinking of Morgan's.
I bet the graders get sick of seeing them.
I recently did some trading with a coin dealer and he made me laugh.
We were doing Morgan's and he said "look in my cases, they are like some sort of plague".
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I recalled something similar to this and searched for it. Found what I was recalling and was 2022. Here are links to two of the responses from KOYNGUY and JohnBCoins (Butler) which mostly support responses above but with different numbers for each.
https://forums.collectors.com/discussion/comment/13196444/#Comment_13196444
https://forums.collectors.com/discussion/comment/13201308/#Comment_13201308
https://youtube.com/watch?v=hYCRaWPlTIE Sophie Lloyd, guitar shred cover of Panama (Van Halen)
https://youtube.com/watch?v=dOV1VrDuUm4 Ted Nugent, Hibernation, Live 1976
RLJ 1958 - 2023
I believe that generally, other than AU58 examples, circulated coins are easier (not harder) to grade than mint state and Proof ones and thus, don’t take as long.
Mark Feld* of Heritage Auctions*Unless otherwise noted, my posts here represent my personal opinions.
Sounds like the title of a song Tom Lehrer could have written and recorded...
As a follow up to New Math
Experience the World through Numismatics...it's more than you can imagine.
If I ever run into them again, I will. I'm not firm on my timely estimates. I do love a good math problem though.
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If a person only had fresh silver dollars to grade, 2000 a day is doable in a 10 hour day sprint. Think guest graders that are paid by coin for a 1-2 week period. As a full time job, forget it.
We've had young eyes grade over 5,000 coins a day, They either burn out, or graduate to other duties. Watch a marathon, you won't see any of the early sprinters win.
Now, consider the data entry of box #, coin#, date, mintmark, variety attribution, lunch, breaks, call of nature, etc.
A hundred coins an hour is a lot, one a minute is average. If PCGS has
graders that claim 2000 a day, I applaud them and to some degree pity them. Life is about balance. I have 3 teenage boys.
Speed and accuracy have to find a symbiotic middle ground. A grading service has to consider both the carrot and the stick.
Speed grading has it's place, but a some point the services most valuable graders break out the book.
Spending years in a dark quiet grading room, not breaking concentration is difficult even if you do what you enjoy.
After 42 years in a grading room, I have seen many types of graders come and go. When I fully retire next year, I guess I'll have certified over 5 million coins for submittors, many at the lowest cost available at the time. J.P. Martin
62 yrs in Coins, 42 yrs Certifying/Grading, CoinWorld's Most Influential People In Numismatics, 1960-2020. 30 consecutive yrs teaching ANA Summer seminar, Numismatic Ambassador award, 1998 Doctorate in Numismatics, Glenn Smedley Award, ANA Governor 2009/2011, Author/ Host of ANA's best selling video's, courses on grading & counterfeit detection. Taught over 1,100 paying students, Secret service agents, San Diego to Boston, Anchorage to Miami, including 2 coin cruise lecturer. many Free presentations. NLG book and video awards. ANA photographer, SEM operator, ASA Appraiser, Contributor to Redbook, Numismatist, Coin World, Numismatic News, ANA Grading Guides, 40,000 Volume Library, Founder ANAAB, ICG, 1995 ANA collector services appraisal/conservation, First full service Ancient coin grading service. Navy 75-77, WIU 77-81, Dealer1981-1984, ANA 1984-1998, 60 year Collector U.S./ 50 Year Ancient coins. ANA Advisory Committee. Life member ANA, ANS. Semi-retired grader in Denver area
There's a ten-year-old PCGS promotional video on YouTube about how they grade coins. I assume it's authentic, since it pre-dates the age of AI-generated slop:
https://www.youtube.com/watch?v=ihLDv2Vc02k
This video agrees with that recollection: coins are graded independently by two different graders; if the grades agree that's a win-win, but if they disagree it goes to a third grader to break the tie.
If we have more recent than ten-year-old experience on the forum, they might confirm or deny whether this practice is still done. If it does still happen, this means that a coin is going to need less time-per-grader. But this kind of quality control makes sense, and reduces the odds of a "someone got dust in their eye" mis-grade.
Roman emperor Marcus Aurelius, "Meditations"
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Nice to see your were posting after hours Mr. Seymour coins