Pop quiz! Test your deductive reasoning

SimonW · July 7, 2026 11:13PM

Here is a Guatemala Real “cob” I bought recently on the cheap. I bought it because I thought I could tell what the date is. Whether you think that’s a worthy endeavor from a collecting standpoint or not is a different question. 😂

What do you think the date is? What rationale did you use to arrive at your conclusion?

It’s fun! Eventually I’ll probably submit it to see if I can convince PCGS of my belief.

*Hint——acsearch is your friend

(Seller’s pics)
What say you?

JohnnyCache · July 8, 2026 2:21PM

Based on the curved shape of the third digit I would eliminate 1, 4, 5 & 7.

Then I'd consider what are rounded at the top, 2, 3, 6, 8 & 9

Then knowing that cobs at Guatemala run from 1733 thru 1753, to the best of my knowledge, I would then eliminate the 2, 6, 8, & 9. That would leave only the 3. So now I am assuming 173X.

The last digit also seems like it could be rounded at the top, though perhaps a little differently than the second digit, so I'd eliminate the 1, 4, 5 & 7 again.

The little notch on the right side at about two o'clock makes me want to guess 6.
So, without going to the acsearch, I'd guess 1736.

*wording edit

TwoKopeiki · July 8, 2026 6:48PM

Looks like 1743 or 1747 to me. Can see the tops of 4 and flat top of either 3 or 7, then rosette after the date, then G of the mintmark (the notched blob)

SimonW · July 9, 2026 9:38AM

@JohnnyCache

I think you’re looking at the wrong part. The “notched” digit you refer to is a G for Guatemala. Left of that is a rosette. Left of the rosette is the last digit of the date, which has a flat top.

I agree with you @TwoKopeiki on all counts. Furthermore I believe it’s a 1743, when comparing images of known 1743 vs 1747. You’ll notice the giant center dot just below the crown, which tends to show up on the 1743 with that size and position. Also, the spacing and size of the rosettes in relation to the date and “G.” The1743 has large rosettes crammed together. The 1747 has small rosettes spaced far apart. Here are a bunch of comparables. I think it looks like a 1743. Anyone agree or disagree?

syl · July 9, 2026 11:53AM

Wow! Someone sure likes cobs. Yes, the OP coin is 43.

Plus00Vltra · July 9, 2026 6:54PM

Proximity of the G mintmark to the pillar, size of rosette, and and spacing/orientation of the elements matches the 1743 G J 1R.

dcarr · July 22, 2026 3:09AM

@SimonW said:

@JohnnyCache

I think you’re looking at the wrong part. The “notched” digit you refer to is a G for Guatemala. Left of that is a rosette. Left of the rosette is the last digit of the date, which has a flat top.

I agree with you @TwoKopeiki on all counts. Furthermore I believe it’s a 1743, when comparing images of known 1743 vs 1747. You’ll notice the giant center dot just below the crown, which tends to show up on the 1743 with that size and position. Also, the spacing and size of the rosettes in relation to the date and “G.” The1743 has large rosettes crammed together. The 1747 has small rosettes spaced far apart. Here are a bunch of comparables. I think it looks like a 1743. Anyone agree or disagree?

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It is not the one above because the 4 touches the ocean and the G does not touch the pillar.
.

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It is not this one (above) either, because the spacing between the rosette and the M does not match.

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SimonW · July 22, 2026 6:08PM

@dcarr said:

@SimonW said:

@JohnnyCache

I think you’re looking at the wrong part. The “notched” digit you refer to is a G for Guatemala. Left of that is a rosette. Left of the rosette is the last digit of the date, which has a flat top.

I agree with you @TwoKopeiki on all counts. Furthermore I believe it’s a 1743, when comparing images of known 1743 vs 1747. You’ll notice the giant center dot just below the crown, which tends to show up on the 1743 with that size and position. Also, the spacing and size of the rosettes in relation to the date and “G.” The1743 has large rosettes crammed together. The 1747 has small rosettes spaced far apart. Here are a bunch of comparables. I think it looks like a 1743. Anyone agree or disagree?

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It is not the one above because the 4 touches the ocean and the G does not touch the pillar.
.

.

It is not this one (above) either, because the spacing between the rosette and the M does not match.

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I see what you’re saying about the spacing on the M. Might the double strike have any bearing on that?
Changed the position of the G in relation to the M? This is the one I would assume it is.

Rexford · July 22, 2026 6:33PM

It is 1743, it’s the same obverse and reverse dies as these two examples. The spacing is the same, any difference mentioned above is due to strike doubling.

dcarr · July 23, 2026 3:51AM

If the M was formed entirely by one striking event and the rosette was formed entirely by a different striking event, then the spacing between them would not match the spacing on the die. This is unusual for design elements that are in close proximity on the die, but it could happen, I suppose.

Rexford · July 23, 2026 9:42AM

@dcarr said:
If the M was formed entirely by one striking event and the rosette was formed entirely by a different striking event, then the spacing between them would not match the spacing on the die. This is unusual for design elements that are in close proximity on the die, but it could happen, I suppose.

It would be a single striking event with die shift, it’s common on older world coins and visible on this coin with the doubled right pillar.

dcarr · July 24, 2026 4:26PM

@Rexford said:

@dcarr said:
If the M was formed entirely by one striking event and the rosette was formed entirely by a different striking event, then the spacing between them would not match the spacing on the die. This is unusual for design elements that are in close proximity on the die, but it could happen, I suppose.

It would be a single striking event with die shift, it’s common on older world coins and visible on this coin with the doubled right pillar.

.

With that far of a shift, and with two separate images, I think the die would have to strike, retract, and strike again. So it is a classic double-strike. A single "striking event" implies a shift while the dies were in contact, like "strike doubling" or "machine doubling" as it is sometimes called. I see no evidence of such a great shift while between the dies.

.

Rexford · July 25, 2026 11:22AM

@dcarr said:

@Rexford said:

@dcarr said:
If the M was formed entirely by one striking event and the rosette was formed entirely by a different striking event, then the spacing between them would not match the spacing on the die. This is unusual for design elements that are in close proximity on the die, but it could happen, I suppose.

It would be a single striking event with die shift, it’s common on older world coins and visible on this coin with the doubled right pillar.

.

With that far of a shift, and with two separate images, I think the die would have to strike, retract, and strike again. So it is a classic double-strike. A single "striking event" implies a shift while the dies were in contact, like "strike doubling" or "machine doubling" as it is sometimes called. I see no evidence of such a great shift while between the dies.

.

That’s just not true, there are many examples of dramatic die shifts on older world or ancient coins that occurred during a single striking event. I think you are approaching this as if it is a modern coin. If it were struck twice there would be overstriking over a large part or the whole of the design rather than one particular area. It’s really beside the point though, it’s from 1743 dies regardless.

Edit: to further explain the above, this coin was not struck in a collar. Without a collar, vibrations/bouncing/shifting of the dies or planchet during strike are not only plausible but relatively common, and can be much more extreme than mechanical doubling on a coin struck within a collar, which is held in place. This is one of the reasons collars are now used.

dcarr · July 26, 2026 1:29AM

@Rexford said:

@dcarr said:

@Rexford said:

@dcarr said:
If the M was formed entirely by one striking event and the rosette was formed entirely by a different striking event, then the spacing between them would not match the spacing on the die. This is unusual for design elements that are in close proximity on the die, but it could happen, I suppose.

It would be a single striking event with die shift, it’s common on older world coins and visible on this coin with the doubled right pillar.

.

With that far of a shift, and with two separate images, I think the die would have to strike, retract, and strike again. So it is a classic double-strike. A single "striking event" implies a shift while the dies were in contact, like "strike doubling" or "machine doubling" as it is sometimes called. I see no evidence of such a great shift while between the dies.

.

That’s just not true, there are many examples of dramatic die shifts on older world or ancient coins that occurred during a single striking event. I think you are approaching this as if it is a modern coin. If it were struck twice there would be overstriking over a large part or the whole of the design rather than one particular area. It’s really beside the point though, it’s from 1743 dies regardless.

Edit: to further explain the above, this coin was not struck in a collar. Without a collar, vibrations/bouncing/shifting of the dies or planchet during strike are not only plausible but relatively common, and can be much more extreme than mechanical doubling on a coin struck within a collar, which is held in place. This is one of the reasons collars are now used.

.

I have struck a lot of coins, including many cobs (without collar). Never have I observed anything like that sort of doubling without a true double-strike.

A drop-hammer press could potentially strike a coin, bounce a little (allowing the coin to shift under the die while not in contact with the die) and then come down again. The second impact would be lighter than the first. But I would still classify that situation as a "double strike", if the dies separated enough for there to be space for the coin to shift laterally.

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Rexford · July 26, 2026 3:12AM

@dcarr said:

@Rexford said:

@dcarr said:

@Rexford said:

@dcarr said:
If the M was formed entirely by one striking event and the rosette was formed entirely by a different striking event, then the spacing between them would not match the spacing on the die. This is unusual for design elements that are in close proximity on the die, but it could happen, I suppose.

It would be a single striking event with die shift, it’s common on older world coins and visible on this coin with the doubled right pillar.

.

With that far of a shift, and with two separate images, I think the die would have to strike, retract, and strike again. So it is a classic double-strike. A single "striking event" implies a shift while the dies were in contact, like "strike doubling" or "machine doubling" as it is sometimes called. I see no evidence of such a great shift while between the dies.

.

That’s just not true, there are many examples of dramatic die shifts on older world or ancient coins that occurred during a single striking event. I think you are approaching this as if it is a modern coin. If it were struck twice there would be overstriking over a large part or the whole of the design rather than one particular area. It’s really beside the point though, it’s from 1743 dies regardless.

Edit: to further explain the above, this coin was not struck in a collar. Without a collar, vibrations/bouncing/shifting of the dies or planchet during strike are not only plausible but relatively common, and can be much more extreme than mechanical doubling on a coin struck within a collar, which is held in place. This is one of the reasons collars are now used.

.

I have struck a lot of coins, including many cobs (without collar). Never have I observed anything like that sort of doubling without a true double-strike.

A drop-hammer press could potentially strike a coin, bounce a little (allowing the coin to shift under the die while not in contact with the die) and then come down again. The second impact would be lighter than the first. But I would still classify that situation as a "double strike", if the dies separated enough for there to be space for the coin to shift laterally.

What you described is the same physical process that occurs with some forms of machine doubling, just to a greater degree since there is no collar.

“Machine Doubling is the product of die instability and displaced energy from the original strike that involves either a die rebounding off of the surface of the coin . . . In the extreme it can grossly distort devices or in some cases mimic a double strike.”

https://www.error-ref.com/multiple-machine-doubling-in-one-direction/

There is a name for the type of machine doubling that involves a bounce and shift, without dragging/smearing the design: “push doubling.”
https://www.error-ref.com/push-doubling/

If it were physically struck twice, it would have doubling of relatively uniform strength and covering most or likely all of the design, instead of just in one portion of the design (which implies that when the dies/planchet bounced/ vibrated/shifted, they naturally impacted again at a slight angle). In addition, on the noted coin there is a corresponding fade inward towards the area where the doubling departs from the design, with the strike on the die shift becoming stronger towards the edge (aka where the pressure from the dies impacting the coin was stronger, because of the angle at which they struck). This makes very logical sense as strike doubling, but not very much as a double strike.

Because of these physical characteristics and the fact that it was not physically struck twice, such a coin would not typically be classified as “double struck”. For instance, NGC would call an ancient coin with this issue “die shift”, which they write on their holders. On a world coin like the one mentioned here, neither NGC or PCGS would call it a mint error for “double struck”, they would simply not note the problem as it occurred during a single press of the dies. I’m familiar with the standards on this because I worked as a grader.

SimonW · July 26, 2026 5:05PM

My assumption before this conversation is that it was struck, it looked like crap, so they struck it again. Some of the original strike was obliterated, much of it remained.

dcarr · July 28, 2026 8:00AM

@Rexford said:
If it were physically struck twice, it would have doubling of relatively uniform strength and covering most or likely all of the design, instead of just in one portion of the design

.

For flat machine-made planchets, that tends to be true.
But if the cob blank is not flat (typical) and/or the dies are tilted off the vertical axis, the type of doubling seen on the subject coin is a result of multiple striking.

If you have one, please post a picture of a coin with the widest doubling that is certified as "die shift".

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Pop quiz! Test your deductive reasoning

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