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 Replies: 13 / Views: 3,977 |
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Valued Member
United Kingdom
179 Posts |
Hello everyone, I purchased a lot of Canadian silver from an auction site (you know the one) and while I was going through the 1968 quarters I noticed that one was over weight at 6g exactly. The other coins are weighing around 5.8g so I believe my scales are calibrated correctly. I would have put this down to a thick planchet and moved on but the coin to my eye also looks more like an 80% (when compared to a 1966) than a 50% of the same year. So what do you guys think? Have any 80% 1968 quarters been documented? I can't find anything through Google but my suspicion is that this may just be a quarter on the heavier side of tolerance. As a side query, I can find information online stating that 1967 (80%) and 1968 (50%) quarters should weigh exactly the same, so am I right in assuming 1968 quarters were manufactured thicker to compensate for Wight loss from reduced silver content being replaced with copper? If so is their any way to know how heavy a (theoretical) 80% 1968 quarter would be?    Many thanks, Matt (: |
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Moderator
 United States
56855 Posts |
What is the mints tolerance +/-? John1  |
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Pillar of the Community
Canada
3733 Posts |
Charlton states, 1968 .500 silver at 5.83 grams, 1968 nickle at 5.07 grams, and everything earlier at 5.83 grams..
So my guess would be it is just .500, and perhaps a little thicker stock, as there is no silver coins, .800 reported minted at 6 grams.
5.83 grams was the standard weight from the late 1800's all the way up until 1968.
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Pillar of the Community
 Canada
9862 Posts |
Most likely just a heavy quarter.
But 80% is possible.
Stranger things have happened.
You must do a specific gravity test or XRF.
Anything else is just pure speculation.
"Dipping" is not considered cleaning...
-from PCGS website
Edited by DBM
07/11/2021 7:32 pm
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Valued Member
 United Kingdom
179 Posts |
Thank you for your replies, I will try my hand at a specific gravity test and if I get any results I will post back.
All the best,
Matt :)
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Pillar of the Community
United States
2869 Posts |
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Valued Member
United Kingdom
179 Posts |
Hi guys, I have completed a specific gravity test on my coins and it looks like the coin in question is just a thick 0.500 coin.
My results probably aren't very accurate but they do give a clear result when comparing my coin against others of known silver content.
The question coin has a specific gravity of 9.96 compared to an average of 9.94(+0.017/-0.030) for known 0.500 coins and 9.99(+0.006/-0.009) for known 0.800 silver coins.
Interestingly I did get a more consistent result from older 0.800 coins so perhaps metal mixes for 1968 0.500 silver coins are more variable than expected? My experiment was quite crude so I can't make any real judgement on that, however, it may explain why my question coin seems to sit between my 0.500 and 0.800 results.
Thanks again for your interest, I would like to know of you have anything too add.
All the best,
Matt :)
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New Member
Canada
13 Posts |
Your 1968 quarter is most certainly a heavier .500 quarter.
Here in Canada, I found a few 1968 silver quarters coin roll
hunting, and yes, I did find 1 or even 2 x 1968 quarters that
weigh as much as 6g, and with a bit of wear! I found one
recently... All the 1968s I got ping as .500 silver, but I have always
questioned myself if any "transitional error coins" were made 80%
in 1968. The composition has switched from 80% to 50%
sometimes in mid-67 (so both compositions exist that year,
for 10 and 25 cents) so I wonder if any lost 80% planchet has
benn mixed in with newer 50% stock and survived until 1968...
Even Mint employees would have a hard time finding such an error
because it would be detected only by pinging it in a quiet environment,
and even then, not everyone can distinguish 80% ping from the 50%...
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New Member
Canada
11 Posts |
 There is one that I know of. It weighs 5.93 grams. |
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New Member
Canada
13 Posts |
Well, I wouldn't totally trust this machine.
This model seems to be able to scan the surface only,
and you need the PRO version to scan in depth.
An easy way would be to ping-test it, and compare the sound to a
1966 (or before) and another 1968.
Of course, it would be a quite interesting discovery if it really tuns out to be 80%, but my doubts persist until further testing.
When I saw your machine, I thought it would be great for me as well, and researched more on YouTube and someone makes a demo of it, and tells the PRO version is more complete, and even then, not 100% perfect.
Unfortunately, they tell the PRO doesn't have the 80% silver setting, so it slowed me down a bit, because of course, most of my coins are Canadian, so 80%, but also some 50% in 1967-68. They tell the machines have coin type databases. The Classic, like the one you have does have the 80% setting, but does it also have a 50% setting? I believe they have their limits, and nothing is worth a ping test, and to really make sure, a gravity test. The XRF might certainly work as well, but the machine is very expensive...
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New Member
Canada
11 Posts |
The shop where I buy my junk silver owns the sigma metallics machine. It doesn't have a 50 % program.The best way to find out the capabilities of the sigma metallics is on their website. I have found an xrf machine at a pawn shop and my 1968 quarter tested 79.02 % silver, 20.98 % copper.
I would have answered sooner but I got sepsis and survived but have some complications that I have been dealing with.
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New Member
Canada
13 Posts |
That's interesting your XRF machine reports this 1968 close to 80% silver. What are the results from your XRF machine if you test another silver 1968, and then a 1966 or earlier? If all other 68s get result close to 50% silver, then this one may in fact be a 80% 1968. However, having your coin in person, I would ping test it, compared to other 68s, and pre-1967s to compare. If your hearing can detect the difference, that's a big asset...
Let us know the XRF results for these other quarters, as well as the ping, if you can.
Luc
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New Member
Canada
11 Posts |
Pawn shops xrf machine. Not mine.  The shop keeper took this photo with my camera. Edited by Beekeeper
05/15/2026 10:05 pm
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Valued Member
United States
460 Posts |
Here is a 1968 Dime struck on an 80% silver planchet so I am sure there are quarters out there too.  |
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Replies: 13 / Views: 3,977 |
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Posted 07/11/2021 7:26 pm
