ordinary chondrites

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Chondrules and metal grains on a sawn face of an unnamed chondrite (probably H5) from northern Chile. This photo was taken with natural light from a north-facing window on a sunny, clear day, so it looks a bit blue. Millimeter scale in background.

Here's a sawn face of another unnamed (L?) chondrite showing metal grains and chondrules. This photo was taken with light from a high-intesity desk lamp. I rebalanced the color to make the gray background be gray. Millimeter scale in background.

Ordinary chondrite pebbles found in the Sahara desert. Most are broken, but a partial fusion crust is intact on many of them. Notice that despite that all of them contain metal, they are not rusty colored.
Three views of the same stone, another unnamed ordinary chondrite (probably H chondrite) from northwest Africa.

Above left
: The unspectacular weathered exterior in direct sunlight.

Above right
: A polished, sawn face in direct sunlight. All the dark areas are alteration rims (rust) around the metal grains.

: The same face illuminated by a north-facing window. The metal grains are more obvious in this view. The rock looks grayer than it actually is in this view because of the polish and blue lighting.

It is likely that this meteorite fell thousands of years ago.

This meteorite violates a number of the recognition principles that I stress in "Some Meteorite Realities." There is no obvious fusion crust. The surface is not glassy or shiny; there are no regmaglypts. The exterior has some ridges and one point. It's clearly a broken fragment of a larger meteorite. If you look closely at the image on the upper left (click on image to enlarge), however, there are shiny metal grains along all the protuberances (points, ridges) because these areas have been abraded from handling. Also, the specific gravity is 3.42, well within the range of ordinary chondrites.

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*See the density web page for a tabulation of the relative abundance of different kinds of meteorites.

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.