hematite concretions

concretions

Hematite concretions or nodules, sometimes called ironstone concretions, are often mistaken for meteorites because their shapes catch people's attention and they are denser than most rocks. Concretions come in a wide variety of bizarre shapes. Sometimes they're shiny on the surface, which might give the impression of a meteorite fusion crust. Note that while a hematite concretion is rich in iron, it is not magnetic. Clicking on some of the smaller images will bring up enlargements.

Below are some solid hematite concretions found near Wentzville, Missouri. Thanks to Joel for the photos.

Below are some more hematite concretions from the country of Georgia. Thanks to Besik for the photos.

Here are some from China. Thanks to Julia for the photos.

Here are some more from the U.S. Thanks to Cary for the photos.

Here are good ones from Isabelle, who found hers in Australia (left), and Jean, who found hers in Massachusetts (right).

Thanks to Micah, here are two views of another one from Missouri.

Thanks to Theresa for two views of a concretion from Texas.

Thanks to Ben for these two views of a hematite concretion

Thanks to Ron from Missouri for these two holey hematite concretions.

Thanks to Christine for this one.

Thanks to Adam for this fine specimen.

Thanks to Mark for this one.

Here's a likely candidate, from Peru! It resembles meteorwrong no. 194. Thanks Jon.

Sometimes hematite makes coatings on other rocks. Thanks to Scott for this one.

Here are two other examples hematite coatings. Thanks Tom and Søren.

Some of the rocks in our Photo Gallery of Meteorwrongs are also hematite concretions:

024 | 046 | 055 | 152 | 155 | 170 | 174 | 186 | 189 | 194 | 205 | 241

See some "cannon ball" concretions

Hematite is easy to identify because it makes a red streak. Also, hematite concretions are denser (heavier for their size) that any kind of stony meteorite or most other kinds of earth rocks. For example, the specific gravity of an ordinary chondrite (the most common kind of meteorite) is about 3.9 whereas the specific gravity of a hematite concretion is 4.5-5. For a good discussion of how to measure specific gravity, click here.

Below are some websites that discuss how concretions form and that have photos of concretions:

Katz | Mozley

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.

e-mail: korotev@wustl.edu

METEORITE OR METEORWRONG?

concretions