Is there a way to know the silver content, ei .500, .750, .999? I've read Tips and Tools and other places. They all tell you how find if it's silver but not how to tell how much. Item in question is not in Numista, it is not a coin it is a Exonumia and not listed but is silver. Netherlands, 10 Leeuwendalder 700 year Stadsrechten. Got it on a swap and swapper didn't know anything about it except it was silver.Thanks.
Do you have $1,000 laying around? https://www.sigmametalytics.com/pmv-original
This tool was $600 before the WuFlu, now I don’t think you can’t get it for less than $1,000. Dealers use it for verification purposes, I’ve borrowed one before, and it’s not that easy to use unfortunately.
The sg test Matt mentions below will probably not be accurate enough to give you a percentage. There’s a lot of fractional math involved, and additionally you’d need a very accurate and reliable scale. The sg test can (most times, but not always) prove silver vs non-silver, but percentage of silver would require knowledge of exactly what the non-silver fraction is, it’s weight, etc.
I’ve never done it but I think I’ve heard some people talk about a specific gravity test or something like that not sure how it works but might be worth looking into.
Quote: "gyoschak"Do you have $1,000 laying around?
https://www.sigmametalytics.com/pmv-original
This tool was $600 before the WuFlu, now I don’t think you can’t get it for less than $1,000. Dealers use it for verification purposes, I’ve borrowed one before, and it’s not that easy to use unfortunately.
The sg test Matt mentions below will probably not be accurate enough to give you a percentage. There’s a lot of fractional math involved, and additionally you’d need a very accurate and reliable scale. The sg test can (most times, but not always) prove silver vs non-silver, but percentage of silver would require knowledge of exactly what the non-silver fraction is, it’s weight, etc.
Thanks but I guess not, besides not that important. I like the coin and that's why I got it. But does give my an idea, next time I'm out maybe could take to a place that buys gold and silver. I'm in Germany so don't know.
Quote: "Myeackle"I’ve never done it but I think I’ve heard some people talk about a specific gravity test or something like that not sure how it works but might be worth looking into.
Matt
Thanks, I looked in the Tip and Tool here and it shows how to do 'Measuring the density' and that only tells you what it's made out of but not how much, I think. Is that what you talking about? Haven't heard of the 'Gravity Test'
Quote: "Myeackle"I’ve never done it but I think I’ve heard some people talk about a specific gravity test or something like that not sure how it works but might be worth looking into.
Matt
Thanks, I looked in the Tip and Tool here and it shows how to do 'Measuring the density' and that only tells you what it's made out of but not how much, I think. Is that what you talking about? Haven't heard of the 'Gravity Test'
Specific gravity is just another name for density (when density is given in grams per cubic centimeter).
Quote: "Myeackle"I’ve never done it but I think I’ve heard some people talk about a specific gravity test or something like that not sure how it works but might be worth looking into.
Matt
Thanks, I looked in the Tip and Tool here and it shows how to do 'Measuring the density' and that only tells you what it's made out of but not how much, I think. Is that what you talking about? Haven't heard of the 'Gravity Test'
Specific gravity is just another name for density (when density is given in grams per cubic centimeter).
Would that tell me how much silver? The density test would tell just that it is silver or am I wrong?
Quote: "Would that tell me how much silver? The density test would tell just that it is silver or am I wrong?"Would that tell me how much silver? The density test would tell just that it is silver or am I wrong?
Provided the coin is made solely of silver and copper, it would be easy to calculate the percentage of each from the specific gravity/density.
Ag - 10.5 g/cm3
Cu - 8.9 g/cm3
x - your coin density
%Ag = (x-8.9)/1.6
You are mostly right. Having a density near 10.5 g/cc is a very good indicator that the coin is pure silver vs. a silver looking cupro-nickel coin with a density of 8.9 g/cc. Part of the problem with this test is its accuracy (although with proper equipment it can be very accurate) and part because there are other metals/alloys that can have a density similar to silver. A coin made of columbium would look like silver and have nearly the same density. However, of course, nobody makes coins from columbium so you don't even consider that possibility. When other elements are alloyed with silver the resulting density changes. The exact change will depend on which elements, how much of each and the resulting crystal structure. You can't just use the individual densities and proportions. A good example of this is the US Jefferson Wartime Nickel with a composition of 56% Copper, 35% Silver, 9% Manganese. The exact percentages of each element was adjusted to give a density exactly equal to the cupro-nickel 5 cent coin it was replacing. Silver coins are many times alloys of just silver and copper. For this alloy system, the more copper the lower the density as shown in the following graph. So, if you're sure your coin is an alloy of silver and copper (only) and you accurately measure the density and get 9.5 g/cc you know it's about 42% silver. A slight error in measurement or a different silver alloy and all you can deduce is that it's probably a "silver" coin.
I know that's a lot of words to say the density test is not a very good test to determine percentage of silver in a coin.
Quote: "iiruig"I think you will be able to determine if the silver is 500 or 999 from this test. It won't give you the exact number though.
https://en.numista.com/numisdoc/determining-the-metal-of-a-coin-27.html
I believe if it is 999, it will be at 10.5, and if less, it will shift down.
You can try also with some other coins that you know the % first to test.
Have fun!
I agree if you can measure the weight in water very accurately. That's a difficult thing to do and lots of room for error. A slight touch of the side, a small trapped air bubble, calibration of scale slightly off, etc. can cause a change in reading and a small change can make a large difference. For instance, for a 5.75 gram coin, a difference of only 0.05 gram on the weight in water will change the density from 10.45 (.999 Ag) to 9.7 (.500 Ag).
Quote: "iiruig"I think you will be able to determine if the silver is 500 or 999 from this test. It won't give you the exact number though.
https://en.numista.com/numisdoc/determining-the-metal-of-a-coin-27.html
I believe if it is 999, it will be at 10.5, and if less, it will shift down.
You can try also with some other coins that you know the % first to test.
Have fun!
I agree if you can measure the weight in water very accurately. That's a difficult thing to do and lots of room for error. A slight touch of the side, a small trapped air bubble, calibration of scale slightly off, etc. can cause a change in reading and a small change can make a large difference. For instance, for a 5.75 gram coin, a difference of only 0.05 gram on the weight in water will change the density from 10.45 (.999 Ag) to 9.7 (.500 Ag).
Agree, but if the scale is up to 0.01, it should be doable. And, again, it is better to test it with the known coins. And if it works, then there is a big chance it will work with that token.
Quote: "iiruig"I think you will be able to determine if the silver is 500 or 999 from this test. It won't give you the exact number though.
https://en.numista.com/numisdoc/determining-the-metal-of-a-coin-27.html
I believe if it is 999, it will be at 10.5, and if less, it will shift down.
You can try also with some other coins that you know the % first to test.
Have fun!
I agree if you can measure the weight in water very accurately. That's a difficult thing to do and lots of room for error. A slight touch of the side, a small trapped air bubble, calibration of scale slightly off, etc. can cause a change in reading and a small change can make a large difference. For instance, for a 5.75 gram coin, a difference of only 0.05 gram on the weight in water will change the density from 10.45 (.999 Ag) to 9.7 (.500 Ag).
Agree, but if the scale is up to 0.01, it should be doable. And, again, it is better to test it with the known coins. And if it works, then there is a big chance it will work with that token.
I agree; it should be doable...if one is very careful with the weight in water. Of course, the larger the coin the more accurate it will be. So...tomorrow I'll set it up and compare a 1942 NZ 3 pence (50% Ag) with a 1917 UK 3 pence (92.5% Ag) (coin weight on low end 1.4 g) and a 1964 Kennedy 1/2 (92.5% Ag) with a 1967 Kennedy 1/2 (40% Ag) (coin weights on high end 12.5/11.5 g).
Thank you all that replied, some went though great length to explain how it's done. I didn't know you had to be a mathematician in order to be a coin collector. My head is about ready explode. But thank you for the information. In the end and hours of searching the web, I did find it in the internet and found it was .999, 12.5 grams. It's not a coin it's a medal so not in Numista, which is OK and I knew that before I swapped for it.
Thanks again for all that answered. This a great place to get all kinds of information and a great site to record my coins and Notes.
Stay safe
I did the experiment I discussed above and here are the results I got. I did each coin 3 times and averaged the density results. I then used Dejan's formula to calculate the percent silver and compared to the actual mint stated percent silver.
Large coin
1964 US Kennedy 1/2 dollar - measured density = 10.46 calculated silver = 97.5% actual silver = 90%
1967 US Kennedy 1/2 dollar - measured density = 9.46 calculated silver = 35.0% actual silver = 40%
Small coin
1917 UK 3 pence - measured density = 10.43 calculated silver = 95.6% actual silver = 92.5%
1942 NZ 3 pence - measured density = 9.97 calculated silver = 66.9% actual silver = 50%
Quote: "rsirian1"I did the experiment I discussed above and here are the results I got. I did each coin 3 times and averaged the density results. I then used Dejan's formula to calculate the percent silver and compared to the actual mint stated percent silver.
Large coin
1964 US Kennedy 1/2 dollar - measured density = 10.46 calculated silver = 97.5% actual silver = 90%
1967 US Kennedy 1/2 dollar - measured density = 9.46 calculated silver = 35.0% actual silver = 40%
Small coin
1917 UK 3 pence - measured density = 10.43 calculated silver = 95.6% actual silver = 92.5%
1942 NZ 3 pence - measured density = 9.97 calculated silver = 66.9% actual silver = 50%
So...I guess I am now a believer. It is doable.
Wow! Thanks for confirming it.
AS we can see that test is quite reliable and easily differentiating between 90% & 50% at least.
Status changed to Solved(David52, 20 May 2021, 18:56)
