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insurrection1517
Penny Sorter Member
USA
81 Posts |
 Posted - 02/24/2008 : 20:19:55
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Hello,
Is there anyway to tell a .800 silver/.200 copper 1967 dimes from a .500/.500 dimes?
I understand they are the same weight, but there must be a way to tell them apart.
Thanks!
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fasTTcar
Penny Sorter Member
Canada
94 Posts |
Posted - 02/25/2008 : 08:16:42
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My refiner tells me :-)
I did a melt of $250 face value 67 dimes and quarters and it worked out to be about 80% at 80% and 20% at 50%. YMMV, but the dealers I speak to privately say they keep the 67's for themselves as it has the most upside compared to buy price.
As far as I know, there is no practical way outside of melting them to find out. |
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HoardCopperByTheTon
Administrator
USA
3603 Posts |
Posted - 02/25/2008 : 11:14:39
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If you had a strong enough magnet, wouldn't the 50 percenters have some slight attraction? Maybe you could measure variances in the magnetic field.
Also maybe you could differentiate by running a current through the dime and measuring the conductive resistance. |
If your percentages are low.. just sort more. If your percentages are high.. just sort more.
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horgad
1000+ Penny Miser Member
USA
1349 Posts |
Posted - 02/25/2008 : 12:08:14
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quote:
Originally posted by HoardCopperByTheTon
If you had a strong enough magnet, wouldn't the 50 percenters have some slight attraction? Maybe you could measure variances in the magnetic field.
Also maybe you could differentiate by running a current through the dime and measuring the conductive resistance.
Good point. I bet a Ryedale or other coin discriminator could tell them apart if you tuned them right. Maybe even a good metal detector could tell the difference if you made sure the distance to the coin stayed constant while you waved your wand. |
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NiBullionCu
Penny Sorter Member
USA
92 Posts |
Posted - 02/25/2008 : 12:44:50
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I've seen this question asked many a time, but have never heard any reports of any one successfully able to discriminate between the two without refining.
Here is something I found online:
Schwerter's Testing Fluid is made by dissolving all of the Potassium Dichromate Salt in a solution of 3/4 oz Nitric Acid plus 1/4 oz distilled water.
Testing Below 14 Karat and Base Metals with Schwerter Salts
File a deep notch in the test piece and apply a drop of Schwerter's Solution in the notch. The colour reaction of the solution with the metal will be as follows:
* Brass - Dark Brown
* Copper - Brown
* Nickel - Blue
* Palladium - None
* Gold - None
* Silver Pure - Bright Red
* Silver .925 - Dark Red
* Silver .800 - Brown
* Silver .500 - Green
* Lead - Yellow
* Tin - Yellow
As was previously mentioned, a good discriminator or metal detector may be able to tell.
Or you could build a very sensitive "Wheatstone Bridge" to test with.
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insurrection1517
Penny Sorter Member
USA
81 Posts |
Posted - 02/25/2008 : 13:59:18
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Okay, I guess I can try these methods. I saw a coin discriminator on ebay that someone posted on here a while back, but I'm not sure what is entailed in wiring one of those up. Is it difficult?
I'm not sure if I want to try the testing fluid as I have to file a notch in the coin.
As I understand the Canadian mint produced about 36 million of the .800 silver dimes, and 35 million of the .500 silver dimes during 1967 - all with the fish (mackeral) on the back.
I have about 25 of these dimes, I've accumulated, and am trying to figure out what to do with them. |
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fasTTcar
Penny Sorter Member
Canada
94 Posts |
Posted - 02/25/2008 : 15:28:37
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I have a Ryedale and spent about 20 minutes fooling around with it trying to differentiate, but did not get anywhere.
It probably can be done, but I was unable to do it. |
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HoardCopperByTheTon
Administrator
USA
3603 Posts |
Posted - 02/25/2008 : 15:34:34
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| I don't think the discriminator on eBay or in the Ryedale would be sensitive enough to tell the difference between the 2. I think Reis makes a machine that would, and maybe one of the De La Rue machines that allows you to train it to differntiate metalic content. |
If your percentages are low.. just sort more. If your percentages are high.. just sort more.
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NiBullionCu
Penny Sorter Member
USA
92 Posts |
Posted - 02/26/2008 : 08:21:56
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I can't vouch for the accuracy of this device, but it looks interesting:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=260213939673
quote:
FINE SILVER (100%) Ink will turn black within 30 minutes of exposure.
STERLING SILVER (90%): Ink will turn black within 15 minutes of exposure.
50%-75% SILVER: Thin ink turning black within 5 minutes of exposure.
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Telling .800 1967 Canadian Dimes from .500
