Worn Mexican Coin Identification

The coin looks to be Mexican based on other coins like the 20 centavos, 50 centavos, and 1 peso from the 1920's. I purchased it from eBay with a description of 1921 20 centavos; however, the coin is not the correct dimension. A 1921 20 centavos is 19mm and the one pictured is closer to 24.5mm.  The coin is non magnetic and moves with a magnet so it looks to be silver. I don't have an accurate scale, but its 6 grams plus or minus 1 gram at best.

I have looked through Numista from 1920 to 1930 and I found no coins made of silver that match the dimension. In addition, I looked through a reference book called “The Comprehensive Catalog and Encyclopedia of Modern Mexican” by William Lawrence Hanks published in 1975 and found no match.

At this point I would say its fake, but its odd and wanted to see if anyone had any ideas.

Additional information:

• The coin is 1.4mm thick
• Added a picture of 20 centavos (19mm), 50 centavos (30mm), and the unknown coin (24.5mm). 
• Added a picture of the vernier calipers measuring the coins diameter.

May be a 50 centavos 1921 ?

The only one that more or less matches with your specifications and pictures is indeed the 50 centavos: N#3844

Unfortunately, the placement of the date and the S of CENTAVOS is off:

I do not believe it to be a fake and I agree that it is strange but it cannot be a 1921 50 Centavos as the 1921 50 Centavos has a lettered edge while yours has the proper edge of a 1921 20 Centavos albiet very worn. My question would be how sure are you about the specifications you are providing to us. I am almost certain this is a 1921 20 centavos as was the seller who I believe came to the same conclusion with no intent to decieve.

Your edge in altered light.

Can you show us the diameter of your example relative to a MM ruler?

harryg

 it cannot be a 1921 50 Centavos as the 1921 50 Centavos has a lettered edge while yours has the proper edge of a 1921 20 Centavos albiet very worn. 

Your completely right, my mistake. I was focusing on the specifications and forgot the edge. But for a 20 centavos the given specifications are completely wrong. 

And for the 20 centavos the placement of the S from CENTAVOS is also very far off:

And what about my question about Tonga ?

Frenchlover

And what about my question about Tonga ?

I'm coming to that soon. My mother passed away about 2 weeks ago, so I'm a bit behind right now.

I think we need more specific information from the OP with photos to confirm the information being provided. Exact diameter in MM, weight in grams, and thickness in MM. Please note that as well as the lettered / reeded edge difference, the thickness of the 20 Centavos should be 1.2mm versus 2MM for the 50 Centavos. 

Essor Prof

Frenchlover

And what about my question about Tonga ?

I'm coming to that soon. My mother passed away about 2 weeks ago, so I'm a bit behind right now.

my condolences, the 200+ kilo Tongan king can wait.

Essor Prof

The only one that more or less matches with your specifications and pictures is indeed the 50 centavos: N#3844

Unfortunately, the placement of the date and the S of CENTAVOS is off:

 

Thanks for the graphics, you need to show me how this is done. It's so cool when comparing coins.

harryg

I do not believe it to be a fake and I agree that it is strange but it cannot be a 1921 50 Centavos as the 1921 50 Centavos has a lettered edge while yours has the proper edge of a 1921 20 Centavos albiet very worn. My question would be how sure are you about the specifications you are providing to us. I am almost certain this is a 1921 20 centavos as was the seller who I believe came to the same conclusion with no intent to decieve.

Your edge in altered light.

 

Can you show us the diameter of your example relative to a MM ruler?

 

 

 

 

 

The dimensions I gave are correct and the only reason I'm certain it's not a 20 centavos is because I purchases a few 20 centavos later and found that they are 19mm which is small in comparison to the 24.5mm of the coin in question. Once I'm home later today, I will post the pictures of the 20 centavos to the unknown coin.

Essor Prof

And for the 20 centavos the placement of the S from CENTAVOS is also very far off:

 

Interesting, I didn't notice how different the placement was until your comparison.

harryg

I think we need more specific information from the OP with photos to confirm the information being provided. Exact diameter in MM, weight in grams, and thickness in MM. Please note that as well as the lettered / reeded edge difference, the thickness of the 20 Centavos should be 1.2mm versus 2MM for the 50 Centavos. 

Will update the posting as soon as I get home. Thanks for the interest and help trying to find an answer.

The diameter of the 50 Centavos being 27 mm, it would be necessary to make a homothety when one wants to superimpose the photos.
And to superimpose them, there is a free tool very simple to use: “Gif Creator”.

Mlopez117

harryg

Will update the posting as soon as I get home. Thanks for the interest and help trying to find an answer.

You are welcome. Somehow in my lifetime I grew an affinity for Mexican coinage. I think they are beautiful and simply enjoy any topic related to them. I look forward to additional information.

harryg

Mlopez117

harryg

Will update the posting as soon as I get home. Thanks for the interest and help trying to find an answer.

You are welcome. Somehow in my lifetime I grew an affinity for Mexican coinage. I think they are beautiful and simply enjoy any topic related to them. I look forward to additional information.

Added additional information to the post. Its almost like it fits as a 25 centavos but they were not a thing until later in Mexico.

I have been working on it with the new information and at the moment, I too am stumped. I am considering everything. exonumia, different dates, different denominations, Mexican States, etc. Sorry, I have no real good answer so far. 

Then when you compare the worn 50 Centavos diam 24.5 mm and a standard 50 Centavos 27mm, it's similar :

and you guess “50” which appears in the background 😉

Unfortunately it's not the case for the face 🤔

Frenchlover

 

my condolences, the 200+ kilo Tongan king can wait.

Thank you. I'll meet him today. Not the king himself of course but the question.

Frenchlover

Then when you compare the worn 50 Centavos diam 24.5 mm and a standard 50 Centavos 27mm, it's similar :

 

Yes, that seems to match quite well. So I was thinking maybe a 50 centavos struck on a wrong planchet but then it has to be a foreign planchet since Mexico never struck any coin with a diameter between 24 and 25 mm.

Mlopez117

 

Thanks for the graphics, you need to show me how this is done. It's so cool when comparing coins.

I use photoscape v. 3.7 for this, a very easy, user friendly and free program (http://photoscape.org/ps/main/download.php), with lots of other very interesting features such as cropping pictures:

I especially use the Editor and Animated GIF features (in red). Bottom left you can choose the language (in green).

To make Animated GIF's:

Open the tab Animated GIF (in red)

At left open your maps with pictures, then drag the pictures you want to the grey area (in green)

Click the Add button (in blue)

Other interesting features

Cropping (coin) pictures:

Open the tab Editor (in red)

Select a picture

Open the tab Crop at the bottom and tick the box “Crop round image” (at the bottom in green)

Drag the cursor over the picture. Then drag each of the markers (in yellow) exactly to the rim of the coin.

Click on the Crop button (in blue)

Click on the Save button (in black)

Editing pictures:

Open the tab Editor (on top)

Click on the Home or Tools tab to find an endless variety of possibilities to edit your pictures.

Height-width ratio:

A lot of pictures, especially those made by cellphones have a very bad height-width ratio, as you can see in the example below. To make an animated gif or to add a picture to our catalog, a round coin should be round.

When you open Photoscape v. 3.7 and you select a picture you can see the pixels (in red). This example shows 966 x 914 which means the coin is a bit oval in stead of round. I fix this with MS Paint.

Open the picture in MS Paint

Click on Change format (in green). 

In the pop-up menu FIRST untick the box “Keep height-width ratio” (in blue)

Then change the value horizontally or vertically (whatever is necessary) (in orange)

Save

And the result is:

Equal size:

If you want to compare identical coins in an animated GIF it's important they have exactly the same size. I fix this with Microsoft Office Picture Manager:

Open the picture in Microsoft Office Picture Manager (part of MS Office 2007)

Click on the tab “Picture” and in the pop-up menu on “Change format” (in red)

Then on the left fill in a percentage to enlarge or reduce the picture and click on OK (in blue)

Repeat this till the percentage on top (in purple) is exactly the same as the picture you want to compare with. Always enlarge till the percentage (in purple) is below 100 %. You can check in Photoscape v. 3.7 if both coins have practically the same pixels.

Good luck and I hope this was helpful.

Essor Prof

Frenchlover

Then when you compare the worn 50 Centavos diam 24.5 mm and a standard 50 Centavos 27mm, it's similar :

 

Yes, that seems to match quite well. So I was thinking maybe a 50 centavos struck on a wrong planchet but then it has to be a foreign planchet since Mexico never struck any coin with a diameter between 24 and 25 mm.

Interesting, hypothesis. I wonder what planchet they could have used if that was the case. If they did use the wrong planched then what looks to be excessive wear on the coin may be caused by a shallow press of the die. 

Another question comes up if the above is true, why is it centered almost too good in a wrong die? I need to do more research on how the mint made coins, especial on how the milled edge was somehow produced given the large diameter difference.

Does anyone know if the Mexican mint made coins for other countries?

Essor Prof

Mlopez117

 

Thanks for the graphics, you need to show me how this is done. It's so cool when comparing coins.

I use photoscape v. 3.7 for this, a very easy, user friendly and free program (http://photoscape.org/ps/main/download.php), with lots of other very interesting features such as cropping pictures:

I especially use the Editor and Animated GIF features (in red). Bottom left you can choose the language (in green).

 

To make Animated GIF's:

Open the tab Animated GIF (in red)

At left open your maps with pictures, then drag the pictures you want to the grey area (in green)

Click the Add button (in blue)

 

Other interesting features

Cropping (coin) pictures:

Open the tab Editor (in red)

Select a picture

Open the tab Crop at the bottom and tick the box “Crop round image” (at the bottom in green)

Drag the cursor over the picture. Then drag each of the markers (in yellow) exactly to the rim of the coin.

Click on the Crop button (in blue)

Click on the Save button (in black)

 

Editing pictures:

Open the tab Editor (on top)

Click on the Home or Tools tab to find an endless variety of possibilities to edit your pictures.

 

Height-width ratio:

A lot of pictures, especially those made by cellphones have a very bad height-width ratio, as you can see in the example below. To make an animated gif or to add a picture to our catalog, a round coin should be round.

When you open Photoscape v. 3.7 and you select a picture you can see the pixels (in red). This example shows 966 x 914 which means the coin is a bit oval in stead of round. I fix this with MS Paint.

Open the picture in MS Paint

Click on Change format (in green). 

In the pop-up menu FIRST untick the box “Keep height-width ratio” (in blue)

Then change the value horizontally or vertically (whatever is necessary) (in orange)

Save

 

And the result is:

 

Equal size:

If you want to compare identical coins in an animated GIF it's important they have exactly the same size. I fix this with Microsoft Office Picture Manager:

Open the picture in Microsoft Office Picture Manager (part of MS Office 2007)

Click on the tab “Picture” and in the pop-up menu on “Change format” (in red)

Then on the left fill in a percentage to enlarge or reduce the picture and click on OK (in blue)

Repeat this till the percentage on top (in purple) is exactly the same as the picture you want to compare with. Always enlarge till the percentage (in purple) is below 100 %. You can check in Photoscape v. 3.7 if both coins have practically the same pixels.

 

Good luck and I hope this was helpful.

 

Thanks a million, this will be very helpful.

Essor Prof

 

 

Yes, that seems to match quite well. So I was thinking maybe a 50 centavos struck on a wrong planchet but then it has to be a foreign planchet since Mexico never struck any coin with a diameter between 24 and 25 mm.

I don't think it can be 50 centavos struck on a wrong planchet.  The size of the design on the obverse is much smaller than it would be if a 50 centavos die were used.

 Could it be a 50 centavos coin trimmed down to that size.  

 My condoolences ,Essor Prof.  Sorry to here that. wish you and family well.

ALLRED1950

 My condoolences ,Essor Prof.  Sorry to here that. wish you and family well.

Thank you Daryl, but I have peace with it, we saw it coming and she was 91. My father died six months earlier, that was a much bigger shock. He got sick and less than a day later he passed away, he was 90.

But we can't complain, they could stay in their own house till my father died.

rsirian1

May you make an animation with your pictures ?

I did this morning then left for work before I could upload it. I will later tonight when I get home.

ALLRED1950

 Could it be a 50 centavos coin trimmed down to that size.  

That was my assumption and why I made that picture. The answer is no unless somehow the original design was shrunk.

Frenchlover

 

May you make an animation with your pictures ?

 

OK, full disclosure. I made a terrible mistake.  When I resized and created this picture:

I had thought the 50 centavos coin was the 27 mm one rather than the 30 mm one the OP said it was. So my conclusions were completely wrong. Here is the correct resized comparison:

And a gif:

So ALLRED1950 suggestion is probably true.

Yes,  but does this also explain the wide thickness variation. 50 C =2mm - .20 C 1.2 mm - OP's example 1.4mm. Is it possible the reverse  (obviously) was “shaved” .6mm? Seems like alot. Yes, clearly heavily worn (shaved) but some details are still visible like the partial date and at least the S at the end of Centavos.

Edit : OK, maybe the loss of the rim where the thickness would be the determining measure can explain such a wide variation. Don't mind me, I am just talking to myself now. But I am on board with the explaintion. 50 Centavos trimmed down for whatever reason.

 I think it very possible, the thickness difference. With the rim gone what usually its high point.   

 I love Mexican coins, have from the late 70's. And try to read anything on the forum about them.

rsirian1

 

So my conclusions were completely wrong. Here is the correct resized comparison:

So ALLRED1950 suggestion is probably true.

After your correction I assume a 50 centavos coin struck on a wrong planchet is also still a possibility?

Essor Prof

rsirian1

 

So my conclusions were completely wrong. Here is the correct resized comparison:

So ALLRED1950 suggestion is probably true.

After your correction I assume a 50 centavos coin struck on a wrong planchet is also still a possibility?

Yes, absolutely. I didn't think it was a viable explanation only because of my (mistaken) belief the design was smaller than a 50 centavos die would make.  So, with two options, unless more evidence is found, it comes down to which has the higher probability of being correct (assuming we've discounted the complete fake theory).

I measured the thickness of a 50 centavos coin I had (XF) in 3 places, rim, center, in area with no devices to get a feel for the thickness variation.

Rim = 1.83 mm

Center = 1.64 mm

Field = 1.27 mm

The coin page ( N#1030 ) has a thickness of 1.9 mm.

There's a reason thickness isn't a search option in Numista.

Still scratching my head on how the reeding is on the OP's example.

harryg

Still scratching my head on how the reeding is on the OP's example.

Good question. If it is reeding wouldn't it have been put there during the striking process by the collar? If so, it would have had to been a 24.5 mm collar which Mexico mint didn't use?

This is definitely an interesting puzzle. Comparing ratios between the silver 50-centavo and 20-centavo coins of 1921, a width of 24.5 mm and thickness of 1.4 mm would suggest a theoretical 25-centavo coin. However, a weight of around 6 grams would be too much for such a coin, if it was in fact .720 silver. It should weigh around 4.16 g, or even less because it's so worn.

Now, did Mexico ever produce silver 25-centavo coins of around this size? The answer is yes. From 1869 to 1892, there was a 25-centavo coin (N#18718) with diameter of 25 mm, thickness 1.25 mm, weight of 6.77 g, and reeded edge. However, this coin was .9027 silver, not .720.

I almost wonder if maybe 50 centavos was struck on an older 25-centavo planchet, which would only leave the difference in thickness to explain…

Yes. I pointed out the reeded / lettered edge difference between the 20c/50c earlier in the thread when I was still unsure of the OP's original specifications provided. At this point I think we can agree that this example is an abberition, certainly one of a kind, and not easily explained away with any certainty at all. Perhaps the person who altered it in the first place thought it a good idea to add the reeding after the fact as well, whatever their reasoning. We cant possibly know for certain.

 To me the reeding on the OP coin. Is not reeding. It is not spaced even or in how deep it is. Could be a bur on the tool they used to cut or clip the coin.  Every time they cut the bur transferred a scape on the coin.  

Looks pretty close to the original 20 Centavos pattern to me. even the same spacing although worn. 

wacko

 

I almost wonder if maybe 50 centavos was struck on an older 25-centavo planchet, which would only leave the difference in thickness to explain…

It might also leave the reeding to explain as I posted earlier and Mlopez117 hinted at.

I think everyone agrees that the dies used to make this item were the same as made the 50 Centavos (1919-1945). Yes?

 Yes, it seems to have been made with the dies from the 50 centavos die ,1919-1945.

rsirian1

It might also leave the reeding to explain as I posted earlier and Mlopez117 hinted at.

Sorry, I'm somewhat ignorant about the actual process of minting coins. I had been thinking that if a 25-centavo planchet (or coin) were put within the collar for a 50-centavo coin and then struck (or overstruck), then the edge inscription might not necessarily get put on the coin because of its smaller diameter. For planchets, the reeded edge might get applied separately via an edge incusing machine.

wacko

rsirian1

It might also leave the reeding to explain as I posted earlier and Mlopez117 hinted at.

Sorry, I'm somewhat ignorant about the actual process of minting coins. I had been thinking that if a 25-centavo planchet (or coin) were put within the collar for a 50-centavo coin and then struck (or overstruck), then the edge inscription might not necessarily get put on the coin because of its smaller diameter. For planchets, the reeded edge might get applied separately via an edge incusing machine.

I am ignorant about the process, too. That's why I posted, “If it is reeding wouldn't it have been put there during the striking process by the collar?” with the question mark.  So, in my opinion, the reeding still needs to be explained. Maybe the answer is the reeding in not put on by the collar like you said. For modern US coins, the reeding is put on by the collar.

Although I cannot prove with documentaion specifically that the reeded edge on this coin type was for a matter of fact applied during the minting process, this technique has been going on for centuries all over the world SPECIFICALLY intended to PREVENT the filing or clipping of precous metal coins. With the abundant silver reserves and prolific number of precious metal coins produced in Mexico over the centuries, I think it is safe to assume they were indeed applied during the minting process in 1921. Coin is minted and the dies create enough pressure to force the material into the collar which transfers the reeds to the incoming material. Reeded edge. Almost certainly I would say.