The Numismatic Bibliomania Society



The E-Sylum: Volume 26, Number 33, August 13, 2023, Article 14


Here's the fourth and final part of Greg Bennick's CONECA interview with collector and writer Mike Diamond, covering products of the new coin presses introduced in the early 2000s. Thanks again to Greg, ErrorScope Editor Allan Anderson, and CONECA for making this available here. -Editor

Greg Bennick: I was going to ask you about how the switch to the new coin presses in the early 2000s affected the output of errors. We all heard in the early 2000s that there were going to be no more major errors. That was going to be it. I think that I went into panic mode thinking, What's going to happen to the hobby? Did you find that that was true? What could you say about that period of time and the time since in terms of the errors that have been produced, and which errors have become scarcer?

Mike Diamond: Well, the range of errors definitely contracted. You're not going to get any foldover strikes anymore. You do get some dramatic multistrikes. The range of errors is reduced because the Schuler press is more reliable and because the mint tightened up on allowing these things to escape. They cracked down on the coin wrapping facilities and they told them, You better not let any errors that have escaped get out. They wanted them returned. A lot of errors that are produced, don't really escape. It's been reduced quite a bit from the halcyon days of 1988, 1999, and 2000. It's unfortunate, but certainly there are plenty of errors to satisfy the collector, including a lot of older ones. But, for instance, we have design creep and that's an error that's never been seen before or since, where the die face expands and kind of mushrooms out. I don't think that has anything to do with the Schuler press per se. It just happened to be a one-time flaw in the metal.

Greg Bennick: Interesting. So that's an error that's been discovered in the last handful of years?

Mike Diamond: Yes exactly.

Greg Bennick: Amazing. Well, we've covered a number of things. I'd like to know, what are your own areas of interest in terms of your own collection? And do you have special pieces in your collection that you appreciate and that are your favorites?

Mike Diamond: Well, anything and everything interests me. I'm always interested in the novel and the confounding. I can't really pick any particular error type. I certainly have favorites among the errors that I collect. I like injection impact doubling which is something I discovered. Injection impact doubling is post-strike die contact, leaving small spots of design. With most of the so-called discoveries, other people find them and then they come to me and ask, What's going on? So, injection impact doubling appears on 2000 Sac dollars and some of the America the Beautiful quarter dollars, where it appears that during ejection, the coin is thrust or propelled into the retreating hammer die face, leaving lightly impressed, often wildly offset, highly incomplete design elements.

Greg Bennick: And these are things you have examples of?

Mike Diamond: Oh, yes.

Greg Bennick: That's great. Any other errors from your collection that you appreciate?

Mike Diamond: Well, I have what might be an intentional error. It's a proof dime planchet with a tiny little circular brockage stuck in the center. And an equally tiny area of die struck design on the reverse. It might be an illicitly applied die impression. That's my suspicion. But the strike is pretty strong. The die struck reverse island is not a proof, but it's certainly early die state. I think everybody thought it was a fake because I picked it up on eBay for like $35. But as soon as I saw it, I said, This is probably real!

Greg Bennick: What inspires you and drives you to be so prolific in your writing? You are possibly the most prolific writer on errors and varieties, certainly on errors. Actually, do you focus more on errors or on varieties or both?

Mike Diamond: Well, it depends how you define a variety. You know, people have different definitions of it. I don't do much with double dies, repunched dates, repunched mintmarks, but I do a lot with die errors, which some people would call die varieties. But, you know, any defect involving the die, or the collar, or the strike, or the planchet, it all adds grist to my mill.

Greg Bennick: Absolutely. And that makes sense. And so back to being prolific, you're certainly the most consistent, longest running and highest output writer on errors. What inspires you to do that work?

Mike Diamond: I enjoy making new discoveries and when I write a column, I always want it to contain something that's never been discussed before. I can't always have a brand new error type for every column. But I always like to bring in some angle that hasn't been bandied about before. I'm fascinated by discovering new things. I love discovering new things. I love analyzing them, understanding them, and communicating them. And I'm never at a loss for a topic for a column. In twelve plus years, I've never had a problem coming up with a topic. Occasionally I revisit a topic, but it's always with some kind of new perspective based on either new information or a new understanding of a phenomenon. Plus, I also get paid. (laughs) So that's an inducement to jump into being prolific.

Greg Bennick: (laughs) Well, regardless of the impetus and inspiration, I know that I thank you and everybody involved with errors who reads your columns and who is involved in the hobby thanks you for your output too, because it's incredibly helpful.

Mike Diamond: Oddly enough, I don't get that much feedback on my columns. It's very rare that somebody will write in either asking for more information or questioning what I have to say. It does appear that the grading services completely ignore or, 95% of the time ignore, what I write. They seem to be stuck in the past. A lot of error folks seem to me, that their knowledge seems to have ossified in and around 1990, which seems odd to me.

Greg Bennick: Meaning that the research available at the time is the limit of their knowledge base?

Mike Diamond: Pretty much. Like I say, the grading services don't recognize stutter strikes or design ablation errors or rim restricted design duplication or any of the other things that I've come up with. They have a limited array of diagnoses that they stick with. And if an error kind of resembles it, that's the label they'll plop on it.

Greg Bennick: (Sarcastically) Struck by capped die, for example.

Mike Diamond: (Laughs) Oh my god. That is one of the most abused descriptions! Everything and anything seems to be a die cap or a capped die strike! Multi strikes that aren't multi strikes, and single strikes that ARE multi strikes. I could go on and on. Some people sometimes ask me, How come you don't start your own grading service for errors? And I tell them that the startup costs are formidable. And it's a lot of work for sure, for probably not a lot of money at the rate I would go, because I don't like making mistakes. Sometimes a complex error might take me a while to figure out.

Greg Bennick: Do people send you errors from time to time?

Mike Diamond: Oh, yes. A lot of the time it's damaged coins or real common stuff. But occasionally something really interesting. A fellow, I guess two years ago, sent me a partial flip over counterbrockage, a secondary counterbrockage, which I wrote up in Coin World. I'd never seen that before.

Greg Bennick: I'm glad that you're still making new discoveries. That bodes well for all of us who read your articles.

Mike Diamond: Another example is this woman who came up with the 1999 cent with the mule clash. She didn't know what she had. She presented it to Joe Cronin's Facebook group. As soon as I saw it, I knew what it was, even though I'd never seen one before. But it was the only thing it could be. She was thrilled, and she sold it for a goodly amount of money.

Mike Diamond at microscope Greg Bennick: So, it was a clash between a cent and maybe a dime die, I'm assuming?

Mike Diamond: The 1999 cent mule clash was a clash between a cent reverse die and another cent reverse die.

Greg Bennick: Oh, I see! Well, you've been most generous with your time. Is there anything that I missed that is quite obvious that maybe I've failed as an interviewer by missing? (laughs)

Mike Diamond: I think you've been pretty thorough.

Greg Bennick: That's good to hear!

Mike Diamond: You know, the discoveries never end. Thank you for the interview. It was a pleasure.

More of Greg's error interviews can be found in previous issues of Errorscope magazine. For more information on the Combined Organization of Error Collectors of America (CONECA), see:

To read the earlier E-Sylum articles, see:

Wayne Homren, Editor

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