1972P Kennedy silver?

1957joe · October 26, 2003 11:17PM

I got a 1972P Kennedy in a roll over the weekend and it looks almost prooflike and it also appears to be silver. Is that possible? How would I know for sure what I have. I wish I had a pic.

XpipedreamR · October 26, 2003 11:18PM

What does the edge of the coin look like?

1957joe · October 26, 2003 11:19PM

it looks silver. no sign of cu clad

XpipedreamR · October 26, 2003 11:36PM

Well, one could check the specific gravity of the coin to see if it corresponds to that of a 40% or 90% silver planchet.

1957joe · October 26, 2003 11:38PM

how do you do that?

FC57Coins · October 26, 2003 11:40PM

I guess anything is possible, but the likelyhood of a silver blank being leftover for two years after the last silver half was minted seems pretty remote. As was mentioned above, weigh it and see what that tells you.

nwcs · October 26, 2003 11:45PM

Could also be plated. How is the strike?

XpipedreamR · October 26, 2003 11:46PM

To test for specific gravity, you do a calculation based on the difference in weight of the object weighed in air and weighed in a solution of known density...you would need special equipment to do this.

Or you could weigh it accurately and compare it to the known weight of 90% and 40% silver halves, and that of a normal clad half.

It probably isn't silver, though, you know

1957joe · October 26, 2003 11:49PM

can anybody tell me the exact weights of the clad, 40% and 90%?????

XpipedreamR · October 26, 2003 11:51PM

90% 12.50g
40% 11.50g
Clad 11.34g

1957joe · October 26, 2003 11:52PM

thanks!

1957joe · October 26, 2003 11:59PM

it weighed in at 11.54g

XpipedreamR · October 27, 2003 12:04AM

Oh well, it was a long shot anyway.

1957joe · October 27, 2003 12:07AM

wouldn't that mean that it was 40% silver clad???

XpipedreamR · October 27, 2003 2:14AM

Oh, wait, it didn't register in my brain that the mass was approximately that of a 40% half because I was expecting it not to be. My first guess would be that the scale is off a little. What kind of scale are you using? Is it properly calibrated/zeroed? We're only talking 160 mg of difference here.

1957joe · October 27, 2003 2:16AM

I work at a place that has a lab and the scale is 100% accurate.

XpipedreamR · October 27, 2003 2:20AM

What you must have is an unauthorized mint product issued in error. Please forward to me for proper handling and disposal

XpipedreamR · October 27, 2003 2:21AM

Seriously, though, at this point I don't know. I'm sure the Kennedy experts will come up with some more information, though!

tjkillian · October 27, 2003 2:23AM

<< <i>I work at a place that has a lab and the scale is 100% accurate. >>

Well, nothing is 100% accurate, but it can be very close. Make sure you weigh it five times, resetting the scale each time. Then take the average of the five weighings. I don't know the tolerances for silver half dollars, but if yours exceed that of that of Clad halves, then you might have a winner. Of course you'll have to send it to PCGS as an error. If it does come back as a silver clad, CA-Ching!!!

Tom

1jester · October 27, 2003 2:33AM

What if it was silver (or chrome?) plated? Wouldn't it then register a bit higher on the scales than a clad? I"m just trying to eliminate the other possibilities. It would be super cool to find an error though!

1957joe · October 27, 2003 2:39AM

I'm open to suggestions as to what to do next! (short of sending it to one of you good collectors)

1jester · October 27, 2003 2:46AM

Just thought of another thing. Even 40% silver clad halves show a clad-line on the edge. It's not as pronounced as on cu-ni clad coins, but it's there and unmistakeable. Does this half show that?

flaminio · October 27, 2003 2:47AM

<< <i>I'm open to suggestions as to what to do next! (short of sending it to one of you good collectors) >>

Send it in for authentification. Any of the Big 3 would be OK -- the slab brand wouldn't make much difference for this sort of error. If it comes back authentic --- CHA-CHING! Ya hit the jackpot. Otherwise, you just wasted $20-$30.

FC57Coins · October 27, 2003 2:50AM

I bet if you slap a picture of the coin on here we'd be able to give you a more educated guess. Otherwise - send it to ANACS and see what they say about it.

mgoodm3 · October 27, 2003 2:53AM

The density of clad should be 8.78 g/cm3, while the density of 40% silver should be 9.44 g/cm3. You've got an accurate measure of the weight. All you need is an accurate volume of the coin to get it's density. Can the lab help you.

XpipedreamR · October 27, 2003 3:03AM

I think it would be hard to get a volumetric device that would be large enough to accomodate a half dollar while being accurate to hundredths of a cubic centimeter, unfortunately.

1957joe · October 27, 2003 3:04AM

our lab does't have anything to measure the specific gravity of something that size

supercoin · October 27, 2003 4:16AM

It sure sounds tantalizing! But my guess is the most likely explanation is that it was plated with something after leaving the mint, and that's accounting for the extra weight.

I would compare it to a 1965-70 half and see if it looks "right". A plated coin will have an unnatural appearance -- no cartwheel luster, and the plating would cover some of the usual marks and abrasions found on a coin.

cladking · October 27, 2003 5:41AM

It sounds about right for a heavily plated coin.

Weight of the coin in air compared to it's weight in water will give an
accurate density.

Conder101 · October 27, 2003 9:09PM

Weight tolerance for a clad half dollar is .454 grams so it is within tolerance for a copper nickel clad half. (Max is 11.8 grams) Going to have to run specific gravity to be sure. If his lab can't do it (and I find that hard to believe) then he can send it to me and I can.

nwcs · October 27, 2003 9:41PM

Could it also have been de-reeded to reduce the weight and then re-reeded and plated? I've heard of that being done before. A lot of work, though. How about the width, diameter, etc. How do they compare against a standard half dollar?

1972P Kennedy silver?

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