can't tell what it is from picture. If you think it is possibly a meteorite, take it to a college & let them look at it. but with you in the room, & don't leave it.
The thumb print impressions look good....it is magnetic ??.... Here's a link that you could sent pictures via email and ask and they should be able to help out more or point you in the right direction.....
..Nice find by your Dad..
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