Can a genuine coin have a ''tolerance + or -'' compared to its catalog weight? If YES,how much may this be?

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Hello! Dear Numista colleagues,today I submit to you & your knowledge 2 type silver coins:

1) 5000 dinars AH1324 (1906) from Iran/Persia [Numista no.29123 ; KM981] with a catalogue weight of 23.02g.

2) 50 sen Meiji era-year 9! from Japan [Numista no.14249] with a catalogue weight of 13.48g.

Is someone of you who saw ''in nature'' a piece of both these coins? They both are rare type or date coins,with very low mintage records!

The question is: How much less than its given weight may have a piece of a somehow circulated coin as to be genuine/real ?!

Please keep in mind that at least the first Iranian coin was not an usual circulating type but was minted more as a gift from the Shah for his anniversary. The 23.02g. is known to be mostly a weight for other circulation types of the 5000 dinars denomination.

Thanks for your experienced opinions!

P.S.: I asked for how much less can a coin have, upon its catalogue weight,as to be still considered a genuine coin?! But,same question for the case it has a weight above its catalogue weight,how much such a ''tolerance'' should be???

Or ''tolerance'' for original mint strikes is not allowed even in special cases(old coins,low mintage records,special strikes,posible mint errors …)?!

Thanks again!

Depends on what the difference in weight is and the grade. But in the case of the 50 sen coin which was made for dignitaries it is very very unlikely that you will accidentally find it on some flea market or antique store. Even in a low coin it is a high 4 figure coin.

Hi again! Dear idolenz,I think that in your answer to me you wish to speak as ''a coin for dignitaries'' about the Iranian 5000 dinars 1906 and not about the 50 sen Meiji (which was a circulation type but with some key dates,among those & with a very low mintage,being the ''year 9'' I am talking about).

The real cases I submit you are:

1) the 5000 dinars 1906 with a weight of 23.59g.,above the catalogue value of 23.03g.

2) the 50 sen year 9 Meiji with a weight of 12.89g.,below the catalogue value of 13.48g.

I checked/verified the coins at a jewelry/pawn shop and both prouved to be struck in silver as they should be!

I have a few other type silver coins in XF preservation condition which show same kind of light ''tolerance'' from the catalogue weight:

Two of those are:

÷ a Yen coin of 1870 Meiji,with 27.15g. instead of 26.9g.

÷ a ½ crown coin 1818 of Great Britain with 14.03g. instead of 14.14g.

As you may see,the differencies of weight in these new cases are even less than for the first 2 coins.

Status changed to Solved (AndiPasculescu10, 20-Jun-2022, 09:43 pm)
Status changed to Opened (AndiPasculescu10, 20-Jun-2022, 09:43 pm)

Just the other day I weighed 58 circulated silver Canadian quarters, dating from 1950 to 1968. The Charlton catalogue (and Numista) list the weight as 5.83 grams, but I found that the quarters ranged anywhere from 5.59 g to 5.99 g. So yes, I guess there can be some variation in weight, and not all of it necessarily due to wear.


I don't know the answer for lesser-circulated coins though. Perhaps some mints (or even just older coins in general) had wider tolerances to be accepted as valid?

Hi & thanks,wacko! So,you also found coins with weight above their catalogue weight… That's very interesting,because if in the case of pieces with a weight less than the catalogue weight this can be explained(from case to case) by wear,such kind of explanation cannot be taken for pieces having a weight above catalogue! So,what is a real,possible explanation in this case (extended to the other situation of less weight,for less circulated coins,preserved XF-AU)?


P.S.: This last question is adressed to all members who will like to respond and not to you,dear wacko,who have already given your personal opinion upon this matter!

Everyone knows that the weight values in Numista and other catalogs are, at best, target or standard weights and, at worst, measurement of a single coin in hand.  No manufacturing method can produce identical products 100% of the time.  There has to be a tolerance on those values for acceptance purposes.  Those tolerances obviously cannot be the same for every coin made by every country in any time period.  One can answer your question only relative to one particular coin.  To come up with a general answer applicable to all coins is impossible.


Let's take a look at the coins currently being produced in the US:


penny 3.11 +/- 0.1 g

nickel 5.0 +/- 0.194 g

dime 2.268 +/- 0.091 g

quarter 5.67 +/- 0.227 g

half dollar 11.34 +/- 0.454


So for these coins +/- 4% is the norm.  I would assume the distribution of weights follow a bell curve so the farther from the target value the less likely that weight would occur.  The chances of finding a US coin at + 4% weight are very small.

Hi & thanks,rsirian1,for your valuable response & opinion! It comes to encounter my own opinion and positive expectations for the existance of a ''mint'' tolerance which varies with the country,coin type,mint,year…

But… this responds only about 50% to my question: As you say(and I have to agree!) this ''tolerance + or - ‘’ differs from coin to coin… That is why I gave 4 examples of coins with a ''fate'' expressly important to me. 

Please,what can you (or another Numista member!) say about those particular coins?

Thanks to all of you!


P.S.: The 50 sen coin has a somehow circulated appearance (not too much), the other 3 coins are in an AU condition (with the special remark that the Iranian coin seems to have been a bit weakly struck).

Keep in mind that the +/- 4% is probably in a US Mint internal procedure/standard based on stacking the tolerances of all the individual variables that goes into a coin such as planchet thickness, diameter, density, etc.  The production method is highly automated.  I would expect the actual variation to be much smaller than 4%.  I would be surprised it it exceeded 0.5%.


I cannot answer your question about your coins.  

Nevermind,rsirian1,perhaps another member will be able to give an answer for my particular 4 coins!

Also,I should like to note that the % of tolerance you give are for modern U.S. coins,struck without any doubts with,again,modern tehnologies… That is not the case for older coins(at least 19-beginning 20-th.century),surelly struck with much less performance & accuracy.


Nevermind,rsirian1,perhaps another member will be able to give an answer for my particular 4 coins!

Perhaps.  Maybe try asking the question in the French forum?


Also,I should like to note that the % of tolerance you give are for modern U.S. coins,struck without any doubts with,again,modern tehnologies… That is not the case for older coins(at least 19-beginning 20-th.century),surelly struck with much less performance & accuracy.

Yes, exactly.  I've already said essentially that.

As stated by others in more or less the same words, the answer to your question(s) depends on a combination of (a) statistical considerations and (b) the effects of wear if there is any.


Weight tolerances of newly minted coins, or coins in mint state long after they were minted are about statistics.    

The weight of circulated coins are about a combination of initial weight tolerances (statistics) and the decrease of weight due to wear.

I think you understand this.


It is surely possible to have a weight above the “catalog value” if the catalog value is the mint specification.  This is about statistics, and has nothing to do with the specific coin in question.  As pointed out by other posters, there is no problem with a coin minted 100 years ago being 2% above the “catalog value” if the catalog value is the mint specification.


You can accept that conclusion or not, as you wish.


The effect of wear is more complicated, but I would consider a weight 10% below the mint specification of a modern coin with light wear to be a problem.


Ultimately, I doubt you are going to get the answers you are seeking here on the forum.  Especially because very convincing fakes are being made that were well within any expected weight tolerances.  

My advice is to spend the money to send them out for certification.

Hi! Thank you,tdziemia,for your reply! I understood very well everything you told me and I have to agree to all your statements!

As I believe you also understood, 

my question for particular coins was for exactly the purpose you pointed: Can someone make a difference between a genuine coin having a ‘’mint tolerance'' in its weight and a well done copy/fake which respects those & same tolerancies?!?

It seems that the unser is no! for this site…

But,I am wondering & also asking you,what other perfect methods has a Grading Comp. (compared to those ''at hand'' for an experienced coin collector) to do a 100% authentification of an old coin (modern or ancient)???

Last but not least,the sending of coins to such a reputable company for authentification has (besides the question I asked just above) a quite difficult procedure & very costly too.

If the coins prouve to be real & of a quite significant value,then perhaps that ‘’action'' worths… If not,everything was an important lost of time & money!


You are talking about some 10000+ $ coins here so the relative price would be cheap.

But like I already said the chance you acquired the real deal is near zero for some. You also have not posted a single pictures or all the other data you usually are asked to provide until now. Judging just by weight is quite hard to impossible … you need many metrics for the determination of authenticity.


Use some image host websites or talk to some other person you know that could assist you if you still have upload problems on Numista.

Hezký den.

    It's a pun-you play with words. 

You want the exact number and percentage? But this is irrelevant in these two cases.


Free and instant:  Bratislava, Prague, Vienna -Within 2 hours by car Prague 3 , Experienced companies will go to the stone shop.

I'll say I went to sell the coin -  ( It is written in the receipt of the material- Do not hesitate to contact us via the contact form or by e-mail. Just send photos of the material)

After the evaluation, thank you, I'd rather keep it at home.

However, I would not like to fly out the window and out of shame and prosecution.


Prague groschen are sold even if the coin is one third or half-when it is a rare variant. The certificate of a specific coin is so far the only guide for expensive or rare coins.

My opinion do not comment, it is mine,,The transfer of $ 5 to China via pay pal is not yet a confirmation of authenticity.,,


Hi,idolenz & all of you dear colleagues!

As you asked me in your last message,I come back with photos + data for the 4 particular coins in question of authenticity. 



IRAN/PERSIA,5000 dinars AH1324(1906):

23.59g. / 36mm. /2mm.thickness /reeded edge



 JAPAN,50 sen Meiji era-year 9(!!!):

12.89g. / 30mm. /2mm.thickness /reeded edge  


JAPAN,1 Yen Meiji era-year 3(1870),type 1: 

27.15g. / 38mm. /2.5mm.thickness/reeded edge




GREAT BRITAIN,½ crown 1818: 

14.03g. /32mm. /2mm.thickness/reeded edge


Besides these,dear idolenz,please tell me where have you picked (estimative) values of more than 10,000 usd. for all 4 coins (or for each coin of the 4 (?!)?

I knew that none of them is worth this amount, even in XF. Perhaps,all 4 could reach some 7000-8000 usd. if in an XF. grade they were (but it is not the case for all of them). That is what I knew! 


The 50 Sen Meiji 9 (yours is a bad fake by the way like I thought) had a mintage of 1,251 for dignitaries and the likes, according to JNDA is valued at 2,500,000 - 700,000 yen (UNC - heavily used). Also this type of 1 yen is a commonly faked coin that also shows clear signs of being a forgery.

Dear idolenz,thanks again for helping me solve the problem!

First,I should like to underline that I verified both these coins of mine at a jewelry shop and they both showed to be made of silver. Fakes/forgeries are not made of precious metals,as far as I know. 

Then,would you please be so kind to tell me:

1) What exactly makes you believe that the 50 sen coin is ''a bad fake''? (besides the fact that it had a low mintage that year; not the only one in this case of low mintages 50 sen coins).

2) What ‘’clear signs of forgery'' shows my 1 Yen 1870 coin? Yes,I know that records show it is a frequently copied type but nevertheless is that sufficient to classify it as a forgery/fake?


What have other years mintages to do with anything? Just compare yours with the example pictures on the coin page and you will see the detail differences and the quality issues (with such a low mintage you will not have die varieties).

The 1 yen is not as clear but like I said it is a very often faked coin and small details seem off and small raised parts indicate a forgery but I can't be 100% sure I don't have the coin in hand.


Also were did you get them and have you paid more then a few bucks for them?

P.S. what tests were made to determine the material?

There certainly are fakes made of silver, of many types.

Jamais l'or n'a perdu la plus petite occasion de se montrer stupide. -Balzac

Dear idolenz,the quality of the 50 sen coin put questions also to me,that is why I asked if someone saw a piece of this special year ''in nature''… Because I had no 100% genuine piece to compare with mine. The Numista catalogue shows a 50 sen piece of another year and I was not sure dies for all the years are the same.

About the 1 Yen coin,so you don't have too ''clear'' signs it is a fake… A frequently forged coin cannot be a proof of a 100% fake/copy.

I purchased both coins we are talking about 13 years ago on internet auctions: Those ended at some 250$ for the Yen coin and much less(35$) for the 50 sen(but not everyone is able to read chinese/japanese numerals and also to know that the coin is a key-date issue ; not all catalogues give collectable values for rarer years,other then for the general type coin).

The verifing tests about the metal of the coins were made by a jewler at his shop,using the special acid they have for such purpose put on the traces the coins' edges have left on a special black stone they also have. The colour of the trace left on the stone by the coin imediatelly turned to RED as it should be!

Hello to you too,Mr.Midnight! Thanks for joining us on our debate!

If so happens and many fakes are made of silver,then please tell me(as I don't know the answer!):

1) What's the interest of the forgerer to manufacture such pieces in cases of not extremely valuable coins(great rarities worth thousands of $) ?!?

2) And,even a more important question,HOW can we then make the difference between a genuine silver coin and its silver copy,well done?


Ehm, I don't know on what page you look but the example coin is a 50 sen meiji 9 on the coin page


For me the signs are clear enough not to buy this 1 yen.


This test is a surface test the coin could be plated or be out of silver. These coins (the originals) are so expensive that even pure silver would be a small expense for the forger if he can even just get have the book value.

Ok.,my friend Idolenz,I saw the link you gave me and things seem to have been clarified for the 50 sen coin… I also had serious doubts on it due to its quality.

But for well manufactured silver copies,I have to repeat the question I asked Mr.Midnight above: How can we then make the difference from an authentic coin and such a well done replica?!? If both are made of silver,of course.


Ping test should determine if it isn't silver throughout.

Hi,my friend Slipstreamed

Thanks to you also for joining us!

Yes,you are right,another method (to determine if a metal is silver or not) is the ''ping test'' but I don't know how much efficient it is! I saw that the jeweler tried something like that and combined with the ‘’acid test'' his conclusion was that it is silver.

For me,sorry,I am very unexperienced in doing a good ''ping test''…

One more thing: Up to now no one of you,my collegues & friends,told me ‘’What methods has a grading service to authentificate 100% a coin,as everyone after that is absolutely convinced of their conclusion?''


Knowledge and access to undoubtful originals with good pedigree. 


Even then there will be a few extreme cases were original dies were used and without destructive testing it won't be possible to determine if it is a fake or not.


‘’What methods has a grading service to authentificate 100% a coin,as everyone after that is absolutely convinced of their conclusion?''


Accredited by both NGC and PCGS.  Why not ask the ones doing it?

Hello,my friend rsirian1! You are absolutely fantastic and you help me a lot with your last piece of information and web link you provided!

I wonder how could you ever discover this grading service just in my country & town I live in, Bucharest/Romania???… Unless you are romanian too! Or not?! I even didn't know that a numismatic grading service acted in my country! Days ago another Numista member asked me if there is a grading coin service in my country and I sincerely answered him that no,there is no such service in Romania. And you…found it!!! Formidable! Many thanks again,my dear colleague!


Andy, why do you post the same messages on both the English and French sites?

Coin variants in English:
In French on Cobra's site (not the same)

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