I agree, definitely not a meteorite. I also agree, pyrite, magnetite or hematite. My understanding is that pyrite does occur naturally as a sphere, a mass of crystals. How big is that thing??? Very curious piece. If you do want to sell it, take it to a rock shop. Bet they'd give you a few bucks for it. I'm not sure how common are the naturally occurring pyrite spheres. Might be quite uncommon, if only in the US. I've seen several that have come out of coal mines.
So, how big is it? I'll take a stab, size of a golf ball (common size).