Half dollar in question

[Igotitbad]

So the only 1980 weighs more than it’s supposed to and has a different sound I’m wondering if it is possibly silver? Also wondering how I could find out? The other half dollar is half the size of the regular one and I’m curious as to why ? Any insight is helpful thanks again!!

[occnumis2021]

no silver. the edge clears that part up.

the stock that the blanks are punched from is rolled out at different thicknesses unintentionally and can be seen often in coinage. i'm not certain where the line is drawn between acceptable and being attribution-error-worthy.

there is weight/diameter etc variance acceptable from the mint of +/- of designated weights.those specs are public.

you will also come across reed variance in size, width, quantity etc. probably dentils too.

the info i have shows post 76 halves at 11.5 grams with a tolerance of .4 or 177.472 grains 6.17 +/-.

diameter doesn't actually show variance on the chart i'm looking at but i thought i recalled seeing some specs somewhere for variance.

[Igotitbad]

Thanks for your reply , no chance it could be 40%?

[occnumis2021]

pretty sure even the 40% are silver on the edges as they are made differently. unless i am mistaken, the 40 and 90% are mixed alloys whereas clad have actual layers and are pressed together or something.

[Igotitbad]

Thank you much I appreciate the insight!