<p>If this is something that you have found (rather than purchased as a meteorite) the chances are very small that it is a meteorite. Even if it is a meteorite, the chances it's a Martian one are even smaller still and none have been found in the United States.</p>
<p>According to the <a href="http://meteorites.wustl.edu/numbers_by_state.htm" rel="nofollow noreferrer">Meteorites in the US</a> page, which draws from the <a href="https://meteoritical.org/" rel="nofollow noreferrer">Meteoritical Society</a> database, only 1821 meteorites have been found in the US over the past 200 years. Of all meteorites found in the world, less than 0.1% are from the Moon or Mars (<a href="http://meteorites.wustl.edu/what_to_do.htm" rel="nofollow noreferrer">source statement</a>, <a href="http://meteorites.wustl.edu/meteorite_types.htm" rel="nofollow noreferrer">graphs of meteorite fractions</a>) and none of these have been found in the US, with the vast majority (99%) found in Antarctica or the African or Arabian deserts (<a href="http://meteorites.wustl.edu/lunar/moon_meteorites.htm" rel="nofollow noreferrer">lunar meteorites)</a>).</p>
<p>There is a long <a href="http://meteorites.wustl.edu/realities.htm" rel="nofollow noreferrer">&quot;Meteorite Realities&quot;</a> page and a shorter, graphical <a href="http://meteorites.wustl.edu/check-list.htm" rel="nofollow noreferrer">&quot;Self-Test Check-List&quot;</a> that it would be good to check and go through before it gets to chemical testing.</p>
<p>If you are determined to get testing done, the same meteorites.wustl.edu site on its <a href="http://meteorites.wustl.edu/metcomp/index.htm" rel="nofollow noreferrer">page on meteorite chemical composition</a> recommends chemical testing by Actlabs; there is more information on what they need (a 5g sample) and the type of tests to ask for on <a href="http://meteorites.wustl.edu/what_to_do.htm#actlabs" rel="nofollow noreferrer">this page</a>. Andesite is a type of basalt formed by volcanism and while it is true that most of the Martian meteorites are basalts (as discussed <a href="http://meteorites.wustl.edu/id/lavarocks.htm" rel="nofollow noreferrer">here</a>), so are a lot of Earth rocks. On the <a href="http://meteorites.wustl.edu/metcomp/index.htm" rel="nofollow noreferrer">chemical composition</a> page, in plots of chemical composition such as silicon dioxide (SiO<span class="math-container">$_2$</span>) vs total iron and magnesium oxide content  e.g. <a href="https://i.sstatic.net/jpWEJ.gif" rel="nofollow noreferrer"><img src="https://i.sstatic.net/jpWEJ.gif" alt="chemical composition plots" /></a>the martian meteorites (red squares) separate from most terrestrial/Earth rocks and the &quot;meteorwrongs&quot; (white circles) due to having higher iron+magnesium content in the form of pyroxene, olivine and ilmenite (from 'Chemistry' section of <a href="https://sites.wustl.edu/meteoritesite/" rel="nofollow noreferrer">How Do We Know That It’s a Rock from the Moon?</a>) However as noted on the basalt page:</p>
<blockquote>
<p>Unfortunately, the only way to distinguish a terrestrial (Earth) basalt from a basaltic meteorite (Moon, Mars, asteroid) is with expensive chemical and mineralogical tests. If you find a basalt, it's probably not a meteorite.</p>
</blockquote>
<p>So I would guess that these additional tests for the contents may be enough to distinguish a non-Earth basalt from an Earth one when the appearance to the eye or under a microscope is very similar (due to the similar formation mechanism via lava). However additional tests needed for trace elements may also be needed (Lunar basalts are Chromium-rich but have much lower concentrations of the alkali elements of potassium, sodium, rubidium, and cesium)</p>

CC BY-SA 4.0
2019-10-11T16:12:09.517Z
2023-06-09T07:01:05.433Z
2023-06-09T07:01:05.433Z
astrosnapper
<p>Only <a href="https://en.wikipedia.org/wiki/Andesite" rel="nofollow noreferrer">two meteorites</a> have been found on Earth that are composed of andesite. They were found at the Graves Nunataks ice shield in Antarctica during a US Antarctic search for meteorites in 2006/07. The meteorites are labelled GRA 06128 and GRA 06129.</p>
<p>Geologically, the samples are unusual because they are rare samples of felsic crustal material and they are extraterrestrial. <a href="http://www.psrd.hawaii.edu/CosmoSparks/April14/crustal-Fe-isotopes.html" rel="nofollow noreferrer">Another thing that makes them unusual</a> is,</p>
<blockquote>
<p>these rocks also have unusual, isotopically light iron isotope compositions (negative values of δ56Fe). In contrast, all other planetary crust materials, including Earth's felsic crustal rocks (granites and andesites on the plot), have heavy iron isotope enrichments (positive values of δ56Fe).</p>
</blockquote>
<p><a href="https://strives-uploads-prod.s3.us-gov-west-1.amazonaws.com/20080013157/20080013157.pdf?AWSAccessKeyId=AKIASEVSKC45ZTTM42XZ&amp;Expires=1599129411&amp;Signature=lGT03CRgN%2FotOPj2hRnO%2FdKL2VM%3D" rel="nofollow noreferrer">Additionally</a>,</p>
<blockquote>
<p>The  low  NiO  and  low  Fe/Mn  of  the  mafic  minerals  in  GRA  suggest  that  its  source  was  depleted  of  Ni  and  Fe  relative  to  a  chon-dritic  precursor.  Such  depletions  in  eucrites  and  Martian  rocks  are  interpreted  to  reflect  segregation  of  metal  via  core  formation;  a  similar  inference  could  be  made for the GRA parent body.</p>
</blockquote>
<p><a href="https://ntrs.nasa.gov/citations/20080013157" rel="nofollow noreferrer">Sourced from a NASA Technical Report</a>.</p>
<p><a href="https://www.newscientist.com/article/dn13456-meteorites-may-be-remnants-of-destroyed-dwarf-planet/" rel="nofollow noreferrer">But</a>,</p>
<blockquote>
<p>The meteorites’ composition has led scientists to rule out the possibility that they are chips off of the Moon, Mars or Venus. And the ratio of iron to manganese does not match that of Earth, ruling out the possibility that it is an old chunk blasted off our planet’s surface that later returned.</p>
<p>By measuring the radioactive decay of elements in the meteorite ...</p>
<p>shown that the rock must have formed around 4.5 billion years ago, when Earth and the other planets were coalescing.</p>
<p>Studying these fragments of a now-vanished object from that era provides a rare window into the early solar system</p>
</blockquote>

CC BY-SA 4.0
2020-09-03T10:52:49.150Z
2020-09-03T10:52:49.150Z
Fred
<p>I'm curious if there is a way to test if this sample might be Martian andesite.</p>
<p>What type of oxygen isotope (or other) test can be done to address this in some way?</p>
<p>As background, any information about such tests at the University of Utah would also be helpful to know.</p>
<p><a href="https://i.sstatic.net/Gxphq.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/Gxphq.jpg" alt="enter image description here" /></a></p>

CC BY-SA 4.0
2020-02-25T08:47:42.590Z
This is Rob biddle.my results on oxygen isotope test was."not a meteorite it happens to be a rock from the ocean floor next to hydro thermal vent".i said give me a week i will explaine why.
Rob B
CC BY-SA 4.0
2020-02-25T13:58:33.780Z
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called2voyage
<asteroids><meteorite><astrochemistry><planetary-science>
Is there a way to tell the difference between earth andesite from Mars
Rob biddle
# Is there a way to tell the difference between earth andesite from Mars

(Asked by: username_0 on 2019-10-11)

I'm curious if there is a way to test if this sample might be Martian andesite.

What type of oxygen isotope (or other) test can be done to address this in some way?

As background, any information about such tests at the University of Utah would also be helpful to know.

[![enter image description here](https://i.sstatic.net/Gxphq.jpg)](https://i.sstatic.net/Gxphq.jpg)

**Tags:** asteroids, meteorite, astrochemistry, planetary-science

> **Comments:**
> **username_1**: This is username_0.my results on oxygen isotope test was."not a meteorite it happens to be a rock from the ocean floor next to hydro thermal vent".i said give me a week i will explaine why.  
> **username_2**: @username_1 Please see here about merging your accounts: https://space.stackexchange.com/help/merging-accounts  

---

## 2 answers

### Answer by username_3 on 2019-10-11. Score: 14

If this is something that you have found (rather than purchased as a meteorite) the chances are very small that it is a meteorite. Even if it is a meteorite, the chances it's a Martian one are even smaller still and none have been found in the United States.

According to the [Meteorites in the US](http://meteorites.wustl.edu/numbers_by_state.htm) page, which draws from the [Meteoritical Society](https://meteoritical.org/) database, only 1821 meteorites have been found in the US over the past 200 years. Of all meteorites found in the world, less than 0.1% are from the Moon or Mars ([source statement](http://meteorites.wustl.edu/what_to_do.htm), [graphs of meteorite fractions](http://meteorites.wustl.edu/meteorite_types.htm)) and none of these have been found in the US, with the vast majority (99%) found in Antarctica or the African or Arabian deserts ([lunar meteorites)](http://meteorites.wustl.edu/lunar/moon_meteorites.htm)).

There is a long ["Meteorite Realities"](http://meteorites.wustl.edu/realities.htm) page and a shorter, graphical ["Self-Test Check-List"](http://meteorites.wustl.edu/check-list.htm) that it would be good to check and go through before it gets to chemical testing.

If you are determined to get testing done, the same meteorites.wustl.edu site on its [page on meteorite chemical composition](http://meteorites.wustl.edu/metcomp/index.htm) recommends chemical testing by Actlabs; there is more information on what they need (a 5g sample) and the type of tests to ask for on [this page](http://meteorites.wustl.edu/what_to_do.htm#actlabs). Andesite is a type of basalt formed by volcanism and while it is true that most of the Martian meteorites are basalts (as discussed [here](http://meteorites.wustl.edu/id/lavarocks.htm)), so are a lot of Earth rocks. On the [chemical composition](http://meteorites.wustl.edu/metcomp/index.htm) page, in plots of chemical composition such as silicon dioxide (SiO$\_2$) vs total iron and magnesium oxide content e.g. [![chemical composition plots](https://i.sstatic.net/jpWEJ.gif)](https://i.sstatic.net/jpWEJ.gif)the martian meteorites (red squares) separate from most terrestrial/Earth rocks and the "meteorwrongs" (white circles) due to having higher iron+magnesium content in the form of pyroxene, olivine and ilmenite (from 'Chemistry' section of [How Do We Know That It’s a Rock from the Moon?](https://sites.wustl.edu/meteoritesite/)) However as noted on the basalt page:

> Unfortunately, the only way to distinguish a terrestrial (Earth) basalt from a basaltic meteorite (Moon, Mars, asteroid) is with expensive chemical and mineralogical tests. If you find a basalt, it's probably not a meteorite.

So I would guess that these additional tests for the contents may be enough to distinguish a non-Earth basalt from an Earth one when the appearance to the eye or under a microscope is very similar (due to the similar formation mechanism via lava). However additional tests needed for trace elements may also be needed (Lunar basalts are Chromium-rich but have much lower concentrations of the alkali elements of potassium, sodium, rubidium, and cesium)


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### Answer by username_4 on 2020-09-03. Score: 3

Only [two meteorites](https://en.wikipedia.org/wiki/Andesite) have been found on Earth that are composed of andesite. They were found at the Graves Nunataks ice shield in Antarctica during a US Antarctic search for meteorites in 2006/07. The meteorites are labelled GRA 06128 and GRA 06129.

Geologically, the samples are unusual because they are rare samples of felsic crustal material and they are extraterrestrial. [Another thing that makes them unusual](http://www.psrd.hawaii.edu/CosmoSparks/April14/crustal-Fe-isotopes.html) is,

> these rocks also have unusual, isotopically light iron isotope compositions (negative values of δ56Fe). In contrast, all other planetary crust materials, including Earth's felsic crustal rocks (granites and andesites on the plot), have heavy iron isotope enrichments (positive values of δ56Fe).

[Additionally](https://strives-uploads-prod.s3.us-gov-west-1.amazonaws.com/20080013157/20080013157.pdf?AWSAccessKeyId=AKIASEVSKC45ZTTM42XZ&Expires=1599129411&Signature=lGT03CRgN%2FotOPj2hRnO%2FdKL2VM%3D),

> The low NiO and low Fe/Mn of the mafic minerals in GRA suggest that its source was depleted of Ni and Fe relative to a chon-dritic precursor. Such depletions in eucrites and Martian rocks are interpreted to reflect segregation of metal via core formation; a similar inference could be made for the GRA parent body.

[Sourced from a NASA Technical Report](https://ntrs.nasa.gov/citations/20080013157).

[But](https://www.newscientist.com/article/dn13456-meteorites-may-be-remnants-of-destroyed-dwarf-planet/),

> The meteorites’ composition has led scientists to rule out the possibility that they are chips off of the Moon, Mars or Venus. And the ratio of iron to manganese does not match that of Earth, ruling out the possibility that it is an old chunk blasted off our planet’s surface that later returned.
>
> By measuring the radioactive decay of elements in the meteorite ...
>
> shown that the rock must have formed around 4.5 billion years ago, when Earth and the other planets were coalescing.
>
> Studying these fragments of a now-vanished object from that era provides a rare window into the early solar system


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