On Thursday, June 8, 2000 at 12:00:00 AM UTC-7, Mary Gallager-Hartman wrote:
Anyone out there ever heard of such a coin? I ask because I've seen one and
can't seem to learn anything about it

--
Bob Hartman
K3YVT

For it to be silver it would have to be a cent struck on a dime planchet meant for a 90% silver proof set. It could could be a clad dime planchet, but would be flatter and thinner cuz the dime is smaller, it also would likely be off center. Most likely the copper plating was removed or not applied well. Not to be a nit picker but the mint has never struck pennies.