Why this rock is probably not a meteorite:

1) Most of the rock is too rough and angular. The smooth coating on top is not a fusion crust, it is a chill skin where the volcanic magma was exposed to air. Note that it is flat, not coating a rounded rock.

2) The density is too low for a meteorite because it is very porous.

3) It's too rust colored.  The iron in the rock has mostly been oxided to ferric iron (Fe3+). When they fall, stony meteorites are not so highly oxidized and are not rust colored.  All iron is metallic (Fe0) and ferrous iron (Fe2+, which is not red). A highly weathered meteorite, one that fell a long time ago and has been buried in the ground, might be this color, however. 
What is it?

This is another basalt (solidified lava), one that is so vesicular that it (1) has a very low density for a rock (it's light in weight) and (2) is known by other names, either pumice (very low density) or scoria (not so low).  Such rocks are often sold as "lava rocks" in barbeque grills and are used for landscaping. See also no. 68.


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.