Coin Community Family of Web Sites
Like us on Facebook! Subscribe to our Youtube Channel! Check out our Twitter! Check out our Pinterest!
Username:
Password:
Save Password
Forgot your Password?


Welcome Guest! Need help? Got a question? Inherit some coins?
Our coin forum is completely free! Register Now!

Coin Weights For Silver Vs Cupronickel

 
To participate in the forum you must log in or register.
Author Previous TopicReplies: 9 / Views: 252Next Topic  
Valued Member
Learn More...
United States
385 Posts
 Posted 02/22/2021  2:29 pm Show Profile   Check Lancek's eBay Listings Bookmark this topic Add Lancek to your friends list Get a Link to this Message
Can a copper nickel coin weigh more than a .925 silver coin of the same diameter, width and even design?

On some 80s New Zealand coins Krause is showing 27.22 for silver proofs and 28.28 CuNi business strikes.
Pillar of the Community
Learn More...
United States
4590 Posts
 Posted 02/22/2021  3:08 pm  Show Profile   Check chafemasterj's eBay Listings Bookmark this reply Add chafemasterj to your friends list Get a Link to this Reply
Huh. I would think that the silver is denser than copper.

I copy and pasted this from a website:

A cubic foot of copper would weigh 559 lb. Silver is even denser than copper, at 655 lb for a cubic foot. Gold is really heavy at 1206 lb for a cubic foot.
Check out my counterstamped Lincoln Cent collection:
http://goccf.com/t/303507
Pillar of the Community
Learn More...
United States
5278 Posts
 Posted 02/22/2021  4:44 pm  Show Profile   Bookmark this reply Add commems to your friends list Get a Link to this Reply
You would need accurate measurements of the thickness of each coin - be careful, many time this dimension is rounded off.

It is possible for a CuNi coin that is thicker than a same-diameter silver coin to weigh more.

Collecting history one coin or medal at a time! (c) commems. All rights reserved.
Bedrock of the Community
Australia
18141 Posts
 Posted 02/22/2021  5:42 pm  Show Profile   Bookmark this reply Add sel_69l to your friends list Get a Link to this Reply
The copper nickel and silver coins could be exactly of the same weight and diameter, as per Mint specifications.

.925 Silver has a higher density than copper nickel by about 15%, and thus the difference in specification will be found in the thickness of the coins by about 15%, the CN examples being thicker.
The CN coins are also usually identified by having finer edge milling.

Careful measurement for thickness with an accurate micrometer screw gauge becomes essential to help with investigations. You may need the assistance of a engineering machine person if you don't have one.

Problems arise in the investigations when there is a difference in the specifications between the silver and CN coins for weight. This problem can be overcome by careful application of arithmetic for density volume weight and diameter, and the use of the micrometer screw gauge.
Bedrock of the Community
United States
17230 Posts
 Posted 02/23/2021  6:39 pm  Show Profile   Bookmark this reply Add Conder101 to your friends list Get a Link to this Reply

Quote:
Careful measurement for thickness with an accurate micrometer screw gauge becomes essential to help with investigations.

But to be meaningful you would need to take a measurement at a couple dozen or more places all over the coin (and not the edge) to determine an average thickness. Trying to measure the "thickness" of a struck coin is an exercise in futility. What you need is to be able to measure the planchet or preferably the blank. Striking pressures can make the thickness of the coin vary. For a copper nickel blank to weight the same as a sterling silver one of the same diameter it would have to be 10% thicker.
Gary Schmidt
Edited by Conder101
02/23/2021 6:41 pm
Bedrock of the Community
Australia
18141 Posts
 Posted 02/23/2021  7:13 pm  Show Profile   Bookmark this reply Add sel_69l to your friends list Get a Link to this Reply
If you need to take thickness measurements on opposing points in the fields of a coin, a specialized type of micrometer screw gauge is needed: one with domed tips on the touch points.
Such instruments are available - usually to be found in materials labs or machine shops.
Pillar of the Community
Learn More...
United States
4390 Posts
 Posted 02/23/2021  8:40 pm  Show Profile   Bookmark this reply Add tdziemia to your friends list Get a Link to this Reply
Yes.
If either the thickness or the relief are different.

No if struck in exactly the same dies.

It is not clear from the original post which of these (if either) applies.
Edited by tdziemia
02/23/2021 8:41 pm
Valued Member
United States
472 Posts
 Posted 02/23/2021  8:55 pm  Show Profile   Bookmark this reply Add Dearborn to your friends list Get a Link to this Reply

Quote:
If you need to take thickness measurements on opposing points in the fields of a coin, a specialized type of micrometer screw gauge is needed:


Something like this can work:

https://www.amazon.com/dp/B077XMTTG...bGljaz10cnVl

Along with a standard micrometer:

https://www.amazon.com/dp/B00Z5KETD...aWNrPXRydWU=
"Tell me and I forget. Teach me and I remember. Involve me and I learn." -Benjamin Franklin
Pillar of the Community
Learn More...
United States
4390 Posts
 Posted 02/24/2021  5:23 pm  Show Profile   Bookmark this reply Add tdziemia to your friends list Get a Link to this Reply
Interesting that you were paying enough attention to notice that. I doubt I would have.

Pretty sure the cupronickel coin must be at least 14% thicker.
Bedrock of the Community
United States
17230 Posts
 Posted 02/25/2021  9:20 pm  Show Profile   Bookmark this reply Add Conder101 to your friends list Get a Link to this Reply
Which would mean for a planchet 2.5 mm thick, the copper nickel planchet would have to be 2.9 mm thick.
Gary Schmidt
  Previous TopicReplies: 9 / Views: 252Next Topic  
 
To participate in the forum you must log in or register.





Disclaimer: While a tremendous amount of effort goes into ensuring the accuracy of the information contained in this site, Coin Community assumes no liability for errors. Copyright 2005 - 2021 Coin Community Family- all rights reserved worldwide. Use of any images or content on this website without prior written permission of Coin Community or the original lender is strictly prohibited.
Contact Us  |  Advertise Here  |  Privacy Policy / Terms of Use

Coin Community Forum © 2005 - 2021 Coin Community Forums
It took 0.62 seconds to rattle this change. Powered By: Snitz Forums 2000 Version 3.4.05