Anybody know what this is?

Do you have a power pole or telephone pole in your yard? That is an auger tooth off of the big auger on a digger derrick truck that drills the holes in the ground to set the poles. I've changed a many of em in the last 43 years! They are originally square out at the tips, and the outer edges get ground off to a rounded edge just like the one in the pic. You can knock them off the auger and flip them over to put the unground edge that's still square on the outside to get more life out of it. There are usually 6 of them on the auger, plus the pilot bit.