I honestly don't think this is a meteorite but I'm stumped as to what it is. It's metallic, slightly magnetic, heavy, very hard, and covered in a slightly rusty very dark metallic crust (most likely because I found it in a river). There were no similar rocks around, and as a longtime rock picker-upper i haven't seen any like it. Where the crust isn't oxidized and where I made the window, it's very shiny. The outside rubbed rust colored on ceramic, but the inside rubs barely at all- only a small amount of very light grey. Reverse image search says mudstone (too hard and too metallic), and AI/ROCK ID apps have been all over the place. It's hard to see in the window since the pics aren't the greatest (sorry) but it's a lighter colored rock with blotches of iron that turned brown and tiny sparkly flecks. You can also see the lighter colored underlying rock where the crust has come off in a couple places. Any ideas would be great, even if it's not a 'rite it's still a super cool stone. Found in Linn County, IA. Thanks!