Why this rock is probably not a meteorite:

This one is intriguing.  It's mostly iron metal and, consequently, it's magnetic.  But the metal grains are rounded, and rounded metal grains don't usually occur in meteorites*.  

When analyzed, the metal was mainly iron, but there was no detectable nickel.  Metal in meteorites contains at least 5% nickel.
What is it?

This object was found in the Mississippi River.  Almost certainly, it's man-made, probably some kind of slag.  We have received many pieces of slag that the finder thought might be a meteorite.

*One viewer of this page did want me to mention (with good reason) that this thing resembles a very rare type of meteorite known as a Bencubbinite or CB chondrite. See photo of Gujba here.


Prepared by:

Randy L. Korotev

Department of Earth and Planetary Sciences
Washington University in St. Louis

Please don't contact me about the meteorite you think you’ve found until you read this and this.