Why this rock is probably not a meteorite:

The dark "coating" is much to thick for a meteorite fusion crust. The finder said that a sharp edge would scratch glass. That means it contains quartz, and quartz doesn't occur in meteorites.
What is it?

Hard to say. I'd like to see this one up close.

Note added later: A correspondant from England said: "We see a lot like this in Southern England on the chalk downs. I even have a piece myself - Somewhere in the dozens of rock boxes I've got. The sharp edges are 'lethal' and can cut up raw meat very very easy." Thanks, Phill.

Göran from Sweden says the same thing - It's flint nodules (dark) in a piece of chalk (light).


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.