Clipped planchet error primer - the Blakesley effect.

coppercoins

Thought I would share this little tidbit of education with the folks here, especially considering the number of new people we have that may or may not have heard of this little factoid of numismatic information.

I was going through some pocket change this evening and ran across a single wheat cent out of thousands of memorials, and that single wheat cent happened to be an interesting little error...it was a clip, and not just a clip, but a straight clip, which is a bit less common than it's curved clip brother. You see, a curved clip can happen anywhere in the sheet - simply by having two rows of blank punches too close to one another you end up with a full row of incomplete blanks when the second of the two rows is punched. A straight clip only happens when the sheet moves too far left or right and the blank is cut off the edge of the sheet.

Anyhow, this particluar little straight clip shows an effect that isn't always present on clipped planchets, but when it is you can just about guarantee its authenticity by it. If you look at the design just opposite the clip (in this case the letters of TRUST) you will see that the design and rim is a bit weak up there. This happens because the rim is rolled up, or "upset" in a mill that rolls the blank around and makes it round and raises the rim for better striking. It works by rolling the planchet around a wheel that has a groove in a trench that the blank won't fit through without crimping it. If you think of a blank being round, it would raise the rim all the way around...but if there were a piece missing, the area opposite the missing piece wouldn't receive the pressure necessary to raise the rim...sort of like an out of round shopping cart wheel with a flat spot....bump, bump, bump as you shop, embarassing you all the way. We've all had that happen and wish we had picked a different cart. Well, in coin making, the Blakesley effect, so coined from the first person to realize and describe the cause of the effect, is the result of a blank being upset that started through the machine out of round...with a clip.

Enjoy, and ask questions...that's the only way you'll learn. Unless people like me hang around way past their bed time writing blather about what interests them.



edited because I'm tired and didn't properly proofread...before posting the first time.

coinnut86

<< Enjoy, and ask questions...that's the only way you'll learn. Unless people like me hang around way past their bed time writing blather about what interests them. >>

I always enjoy your posts coppercoins! Very informative and I always learn something new I'm a rookie when it comes to Lincolns, although they are how I got started in collecting. I almost have a complete circulated set (minus keys) and will eventually buy those at a much later date (I'm poor)

Thanks for the info

DorkGirl

Thank you, best explanation I have ever read.

DNADave

Belated and unofficial POTD

seanq

CD, great job in your post. I know how much you hate having those error coins around, so before you spend it I'll be willing to give it a loving home.


Sean Reynolds

Hyperion

great post !

Crazy4Coins

A straight clip only happens when the sheet moves too far left or right and the blank is cut off the edge of the sheet.

So,...do you end up with a whole row of straight clips...and are they all in the same location on the coin?

PerryHall

<< <i>A straight clip only happens when the sheet moves too far left or right and the blank is cut off the edge of the sheet.

So,...do you end up with a whole row of straight clips...and are they all in the same location on the coin? >>



Don't you also get a straight clip at the end of the sheet?

coppercoins

Good questions, I'll try to answer them, but SeanQ is the resident expert in clips.

A curved clip happens to an entire row on a sheet at once...so if the blanking press is punching 12 blanks at a time you get 12 curved clips if you get one. All or none thing..

A straight clip happens off the side of the sheet, so its rarity would generally be roughly 1:12 to curved clips, but that's even skewed. The answer to the first question, however, is that if you get one straight clip, you're likely to get one per row until they straighten out the sheet.

A clip off the end of the sheet is usually a ragged clip. Looks a bit like a curved or straight clip, but has a ragged edge. These are far less common than the others because these coils they cut blanks from weigh in the tons and can provide hundreds of thousands of blanks per coil...only two rows in all of that could be ragged clips.

As far as I understand it, ragged clips are even less common than a coin with three or four curved clips because the sheets get bunched up and produce all sorts of odd curved clips far more regularly than they run off the end of the sheet.

Sean? How about shedding some more educated light on the subject?

As for the coin, you're right Sean...I don't care about it. Just popped out at me while I was going through pocket change, no less. I did find another wheat in the group, a normal 1956D cent...but only those two wheats out of a group of nearly $40 and one was a straight clip with the Blakesley effect...in AU, no less...now, how rare is that??

seanq

Here is a page CU Forum member MWallace created some time ago, which he has since taken down but allowed me to mirror (and... um... eventually update with new pictures and links... sorry, Mike...).

I'm not sure what the exact ratio would be, but cd is right about straight clips being scarcer than curved. I alsobelieve that most ragged clips are punched from either the leading or trailing edge of the raw sheet, while cleaner straight clips are from the sides. Many of the straight-clipped cents in my collection show aabout a 45-degree taper from one face to the other, I'm not sure why.

The location of a clip on a struck coin is completely unrelated to how or where the clipped blank was created, the blanking and striking operations are completely separate and unrelated.

One other interesting observation - double clips are far more prevalent on the copper-coated zinc planchets produced outside the Mint than they are on pre-1982 copper planchets produced within the Mint. I'd estimated that 80% of the zinc clips in my date set, and easily 50% of all those I've seen, have been double clips, and almost always 90-degrees apart. Either the blanking die now being used is much wider than the one used by the Mint, or the punches themselves are more densely packed.

Lastly, I've cherrypicked a few Lincoln clips from dealers, and even a couple of small ones from my own collection (the 1914 cent I had in my AU wheat set had a small ragged rim clip), but I've never found one in circulation, and never one as large as your coin. The good folks who write the 'Found in Rolls' column in Coin World sold me a few circulated memorial cent clips some time ago, but to my knowledge they've never found a clipped wheat cent either. Yours is a very unusual find.


Sean Reynolds