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 Replies: 28 / Views: 35,546 |
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Valued Member
Canada
386 Posts |
Does anyone know a (non-destructive) way to differentiate between 50% and 80% 1967 silver dimes and quarters ?
I had thought the weight might be different. That is not the case according to my Charlton guide.
Someone suggested a chemical stain test to me. But this will leave a permanent stain on the coin. I think it will tell you that silver is present, but will not be able to differentiate between 50% and 80%.
Nickel coins have a dull thud when dropped and silver coins have a pleasant ring. Do you think there is a noticeable difference in ring frequency between 50% and 80% silver ?
How do jewelers assay various grades of gold and silver when the composition number is not stamped on the pieces? Edited by 1945V
02/05/2009 12:53 pm
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Pillar of the Community
Canada
4227 Posts |
Good question ... I was just looking at some '67 25 cent pieces and wondering the same thing. I'll be watching this thread  |
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Pillar of the Community
United States
2049 Posts |
I believe the weights will be different no?
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Pillar of the Community
United States
2049 Posts |
Nevermind...I was wrong...lol. I guess you would have to do the specific gravity test unless others have an idea.
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Pillar of the Community
Canada
838 Posts |
Specific gravity is simply another way of saying "density".
If the weights are identical (and the volumes are identical -- a safe assumption), then so will be the density.
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Pillar of the Community
Canada
838 Posts |
I have heard that 1967 Canadian silver is taken by dealers/jewellers at a common 65% value. This leads me to believe that there's no way of differentiating between the two without disturbing the metal somehow. The "sound" test is probably the best bet, but it would take a lot of work to get good at it.
Compare a known 80% from pre-67 with a known 50% from 1968, and repeat over and over until/if you hear a difference.
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Pillar of the Community
Canada
1931 Posts |
I'm sure there must be some way to differentiate. I cant imagine that these are easy to sell or buy if there is no way to know what you are getting. I wish I knew what that way would be. lol
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Valued Member
United States
417 Posts |
I think you can tell by the ring (at least that's what I read somewhere).
I've got two '67 dimes which sound different, but could it also be the types of sets they were put in? One is P/L-ish and the other is not.
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Pillar of the Community
United Kingdom
1077 Posts |
If the weight of these coins truly is identical to three decimal places and the percentages of silver in them differ then the volume can not be the same.
Accurate specific gravity will tell you the difference.
If the remainder of the composition is copper the specific gravities are as follows
50% 9.665
80% 10.144
Not a huge difference so your calculations will need to be very accurate!
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Pillar of the Community
Canada
838 Posts |
Yes, very true. I was surprised to learn that the complementary metal is pure Copper here. I thought some Nickel might be present in the 1967-68 50% silver pieces.
The weight and volume COULD be the same (in theory), if the complementary metal has the same density of silver. But in this case, yes, a very accurate specific gravity test might work.
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Pillar of the Community
United States
3098 Posts |
Well, I can hear the difference between sterling and .900...
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Pillar of the Community
Canada
4227 Posts |
Well, chuck a couple at wd1040 ... he'll tell us  |
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Valued Member
United States
405 Posts |
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Pillar of the Community
United States
535 Posts |
The two dealers I have spoken with both told me that there is not an "easy" way to tell the difference. In common practice when they are buying and selling bulk they assume half are 50% and half of them are 80%. (So I guess that is the same as all of them are 65%)
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Pillar of the Community
Canada
598 Posts |
I swear the 80% stuff has a higher, longer lasting ring sound when droppped on a hard surface... when compared to 50%. Quote:
Compare a known 80% from pre-67 with a known 50% from 1968, and repeat over and over until/if you hear a difference.
bibd I really suggest trying this if you want to sort purities. If you have junk silver, the 80% stuff is usually more tarnished, but I would not consider this conclusive proof. After you get your 80% sorted out, you may hafta convince a buyer it is 80%. It may be only you that has the knowledge, and anyone else just 65%s it. Quote:
Well, I can hear the difference between sterling and .900... wd1040 That's a difference of .025 between .900 and .925(sterling). That is truly amazing!  |
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Pillar of the Community
United States
3098 Posts |
Well, I'm listening to a 50c Canadian half from the 1910s and a 63 Franklin. I just found out they're different sizes! Maybe that's why I can hear them.
Anyways, I got a lynx quarter and a old style George quarter and struck them. The lynx one is much lower in pitch, and the George sterling quarter sounds like a flat note... maybe a B flat...
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Replies: 28 / Views: 35,546 |
Posted 02/05/2009 12:58 pm
