Calculating .40 % Silver's Value

0.14792
x 20 - 40% silver halves
2.9584 troy ounces of silver !

$16.72 per ounce
So, 20 - 40% silver halves are worth $49.46

This would be 6/25/08 (Wed) spot price for 1 oz. of silver and the non-numismatic value to these 40% silver halves would be referred to as "junk silver price"..or "melt value".......or something like that !....
Generally they're traded for "cash" and not melted down though !....though there are places to send em' where they do that, it isn't the norm. So, this means that you get an "open market" silver trading price for these !.....10 to 12 x face maybe ?....more ?.......less ?.....it just depends.
I'd just save them for 25 years from now when silver reaches $56.23 an ounce versus the $16.00 - $17.00 it's worth now.

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Just being a Mow-ron !...

If I could only have a nickel for every time that site got nixed by the bad word filter, I'd be rich!

PP, referencing that site is banned here because of a rather unkind spamming incident. The bad word filter on the forum will replace it with "Deleted004" every time.

Huntercav, the .715 figure comes from the fact that $1 face of 90% silver coins (excluding silver dollars) contains .7234 ounce of silver. The assumption is that some silver has been lost due to wear, so the figure .715 is used.

$1 face of 40% silver half dollars contains .2958 ounce of silver.