Smallest diameter/lightest coin in your collection

Following on from a previous request to find the oldest coin with an actual date, I am now interested in finding to smallest coin by weight/diameter you have or maybe know to exist.
Mine is a 1/4 Real from Guatemala dated 1895 (KM#162)
Weight 0.77g
Diameter 12mm

Can anyone beat either of these?

Link to the coin is below

https://en.numista.com/catalogue/pieces8119.html

Can I take this opportunity to thank all of those collectors who responded to my earlier request. Some coins added made mine look brand new.

I can beat the weight:

https://en.numista.com/catalogue/pieces10925.html
https://en.numista.com/catalogue/pieces16380.html

I don't have a coin with diameter less than yours :(
I have 12mm: https://en.numista.com/catalogue/pieces21550.html

Anyway, I'm not collecting small coins :)

Looks like mine right now is a 1965 Turkish 1 Kuruş - 14.04mm x .92mm x 1.02g ( https://en.numista.com/catalogue/pieces1154.html ). That's actually about the smallest by overall dimensions - some are lighter but bigger or thicker... This one's close - https://en.numista.com/catalogue/pieces1789.html

That is an interesting topic. I have many light coins. For example from my home country, Finland, we have 1 penni 1969-1979 km 44a, which weight is only 0.45 g. So that will beat the weight at first. My lightest coin is a Hungarian Quarting 1/4 Denar, weight only 0.12 g. Link here:

https://en.numista.com/catalogue/pieces48166.html

I can't beat the diameter. I don't like these small coins much. Most of them look like cheap coins, which they most often are actually.

At first I was thinking of a Maundy penny, but then I remembered this Greek coin. It's a silver tetartemorion from Ionia, Teos (which is 1/4 of an obol, and an obol is 1/6th of a drachma). So it weighs about 0.23 grams and is 6mm in diameter (it looks like a piece of scrap metal without magnification).




Here it is next to a Guatemalan 1/4 real from 1896.

Wow, the Greek coin is really tiny. I think only dust will beat that. Also love the gold Poland coin. Never heard of it before.
Let's see what else comes around over the next few days, but I think the Greek coin is going to take some beating.

I can beat the diameter twice:

Travencore, 1 cash (1901 - 1910), 10,8 mm:

https://en.numista.com/catalogue/pieces21870.html



Travencore, 1 cash (1885 - 1895), 8,4 mm:

https://en.numista.com/catalogue/pieces57425.html



Edit: Oops, while I was searching the coins and making the scans a few other posts beat me. So the Greek coin still wins. (@steve27: for some reason I never can see your pictures, and only yours. Are there others who have the same problem?).

I don't have the coin myself, but here is a coin that beats the Greek coin:

Travencore, 1/2 chuckram (1809-1910), diameter 5 mm.:

My lightest is 0,5 gram Livonian shilling: https://en.numista.com/catalogue/pieces41643.html

And diameter - I only have one curiosity, with diameter different on each piece. https://en.numista.com/catalogue/pieces66365.html

As part of my maths lesson, diameter is across the circle, whereas the item Jarcek has shown is really length x width, so diameter is not possible. Nice try though.

I knew somebody will come up with the math.

My smallest diameter coin listed on Numista is this Russian wire denga, at 11 mm. I have a few Peter I wire kopeks that go all the way down to 9 mm, but those types are not in the catalog yet.

As for the weight, some aluminium coins can get really light - this one is my lightest at 0.456 grams. The denga I mentioned above is 0.34 grams. But both are beaten by this 16th century pfennig, which apparently has a (nominal?) weight of 0.29 grams (a bit less than I expected, to be honest).
I'm pretty sure that the above-mentioned Peter I kopeks are even lighter.

My smallest coin is certainly my 1949 Polish Grosz:

https://en.numista.com/catalogue/pieces2742.html

At half a gram in weight, it feels like nothing in your hand.

My lightest is :
0.45g
Finland - 1 Penni - 1976 - KM#44a
https://en.numista.com/catalogue/pieces3280.html

And I thought I had a smaller one than this, but according to what I have in the catalogue:
13.5mm
UK - 1/4 Farthing - 1839 - KM#737
https://en.numista.com/catalogue/pieces19766.html

I've always wondered this about these tiny coins we're discussing here, why in the world would countries issue such small coins that could easily be lost?

I do understand that for silver, gold and even copper coins, they were made to have the specific denominations worth of metal in it, but, for example, the 1949 Polish Grosz I posted a link to confuses me. Was a half of a gram of aluminum actually worth one Grosz in 1949?

​I guess what I'm trying to ask is, why not just make them larger if the metals you're using for the coins don't correspond to the actual face value?

Forgive me if its sort of a dumb question.

I will stick with post medieval and the only qualifier I have is an 1836, 1-1/2 pence of William iiii.
Weight - 0.71g, mine weighs 0.69g.
Size - 11mm

Sat in the middle of a modern 5p coin.

Quote: "RTScott78"​I've always wondered this about these tiny coins we're discussing here, why in the world would countries issue such small coins that could easily be lost?
​
​I do understand that for silver, gold and even copper coins, they were made to have the specific denominations worth of metal in it, but, for example, the 1949 Polish Grosz I posted a link to confuses me. Was a half of a gram of aluminum actually worth one Grosz in 1949?
​
​​I guess what I'm trying to ask is, why not just make them larger if the metals you're using for the coins don't correspond to the actual face value?
​
​Forgive me if its sort of a dumb question.

​Historically, because at some point the coins become too large instead.
There was a huge disparity between the worth of silver and copper; the cartwheel penny of 1797 was infamously huge, but its silver contemporary was tiny (12 mm), and from a modern perspective, it's not certain which is better.
Similarly, the US large cent was specifically modified to only contain less than half of a cent's worth of copper; a full cent version would have been, again, unreasonably large. (A version with a bit of added silver for correct melt value was considered and decided to be too complicated.) But even then it was still far too small a denomination to be made directly out of silver.

Meanwhile, and more recently, the prices of all the other metals fluctuated too much; I don't know how much aluminium would actually be worth one grosz in 1949, but however much it was (likely too much for a usable coin, but for the sake of argument), it was liable to be worth two groszes a month or a year later, which would mean that a lot of people would have melted down their coins for scrap metal.
(This almost happened to American 5 cent coins, when a rise in nickel prices made them worth nearly 7 cents in melt value; fortunately for collectors, there were laws that prevented such melting. Nickel prices have gone down since, so those coins are only worth about 4 cents in melt value today.
This did happen to Bulgarian 1 and 2 leva coins from 1923, though the reason was apparently less about the metal value and more about the low availability of aluminium to the common people at all; those coins are very uncommon today.)

And most recently - and really for most of the last century (and at occasional times even earlier) - the answer was fiat money; coins, in general, were not supposed to be worth however much metal they contained, but however much they, and the respective government, said they were worth (much like how banknotes have always worked).
In this case, the size of the coin is not important at all, except that it should normally fall within reasonable boundaries (much narrower ones than historically); many modern fiat coins inherited their size from earlier versions with significant metal value, many others were pretty much chosen for convenience.
Within that setting, the low weight of a typical aluminium coin is the function of its low face value (which correlated with smaller size, for obvious reasons) and low density (as expected of aluminium). The Polish grosz weighs half a gram because that's how much a 15 mm aluminium coin would normally weigh; and it's 15 mm because it's the lowest denomination, so it must be small (and/or because the Soviet 1 kopek, whose size was chosen for a weight of 1 gram, is also 15 mm).

Quote: "January First-of-May"​

Quote: "RTScott78"​I've always wondered this about these tiny coins we're discussing here, why in the world would countries issue such small coins that could easily be lost?
​​
​​I do understand that for silver, gold and even copper coins, they were made to have the specific denominations worth of metal in it, but, for example, the 1949 Polish Grosz I posted a link to confuses me. Was a half of a gram of aluminum actually worth one Grosz in 1949?
​​
​​​I guess what I'm trying to ask is, why not just make them larger if the metals you're using for the coins don't correspond to the actual face value?
​​
​​Forgive me if its sort of a dumb question.

​​Historically, because at some point the coins become too large instead.
​There was a huge disparity between the worth of silver and copper; the cartwheel penny of 1797 was infamously huge, but its silver contemporary was tiny (12 mm), and from a modern perspective, it's not certain which is better.
​Similarly, the US large cent was specifically modified to only contain less than half of a cent's worth of copper; a full cent version would have been, again, unreasonably large. (A version with a bit of added silver for correct melt value was considered and decided to be too complicated.) But even then it was still far too small a denomination to be made directly out of silver.
​
​Meanwhile, and more recently, the prices of all the other metals fluctuated too much; I don't know how much aluminium would actually be worth one grosz in 1949, but however much it was (likely too much for a usable coin, but for the sake of argument), it was liable to be worth two groszes a month or a year later, which would mean that a lot of people would have melted down their coins for scrap metal.
​(This almost happened to American 5 cent coins, when a rise in nickel prices made them worth nearly 7 cents in melt value; fortunately for collectors, there were laws that prevented such melting. Nickel prices have gone down since, so those coins are only worth about 4 cents in melt value today.
​This did happen to Bulgarian 1 and 2 leva coins from 1923, though the reason was apparently less about the metal value and more about the low availability of aluminium to the common people at all; those coins are very uncommon today.)
​
​And most recently - and really for most of the last century (and at occasional times even earlier) - the answer was fiat money; coins, in general, were not supposed to be worth however much metal they contained, but however much they, and the respective government, said they were worth (much like how banknotes have always worked).
​In this case, the size of the coin is not important at all, except that it should normally fall within reasonable boundaries (much narrower ones than historically); many modern fiat coins inherited their size from earlier versions with significant metal value, many others were pretty much chosen for convenience.
​Within that setting, the low weight of a typical aluminium coin is the function of its low face value (which correlated with smaller size, for obvious reasons) and low density (as expected of aluminium). The Polish grosz weighs half a gram because that's how much a 15 mm aluminium coin would normally weigh; and it's 15 mm because it's the lowest denomination, so it must be small (and/or because the Soviet 1 kopek, whose size was chosen for a weight of 1 gram, is also 15 mm).

​Thank you very much for the write up, very informative and explains a lot, especially the comparison made between how banknotes and coins work anymore. It's not about the value of the metal in the coin, or even the promise of equal value metal in exchange for a banknote (Silver & Gold Certificates), it's what the government deems the value of the coins and notes themselves to be.

1848 Gb 1/16 model farthing size 7mm, weight .23grams.

Here's my smallest:



A 1/32 ducat from the city of Nürnberg. It weighs about .1 grams and is about 5mm in diameter.

Hi,
Please check these: http://www.worldofcoins.eu/forum/index.php/topic,25369.msg166911.html#msg166911
Will probably not be easy to find much smaller ones

Maudry,
Thanks for the link. Very interesting coins. We are now very close to coins purely of dust

My smallest coin is coincidently also from my native country:

https://en.numista.com/catalogue/pieces6543.html
Netherlands 5 Cents 1850-87, silver, 12.5 mm, 0.76 grams

My smallest is a Victorian Maundy penny. It's 11mm wide and weighs 0.47 grams.

Quote: "neilithic"​My smallest is a Victorian Maundy penny. It's 11mm wide and weighs 0.47 grams.

​
Ditto. Didn't even consider that one until I saw your post.

My smallest one is probably the 1/4 Real from Guatemala, already shown by Steve27. However I should check the French forum Minimi & Minimissimi Roman coins topic to find such small coins (less than 10mm)