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Hello all.  I am a coin shooter, relic hunter, and bottle digger. I have always paid attention to meteorite stories and think they are cool. But really never made time to look for them. 

Anyway, a few weeks ago I was kayaking on the river. I dumped my kayak at the dock and lost my keys in the water. No problem, I have a fishing magnet and came back later to get them. What did surprise me is finding a stone attacked to the magnet when I pulled it up out of the water. I have never encountered a rock like this before. 

From my limited googling it seems it could be a chondrites. But I am only guessing.

It is 63 grams. It has been in the water a long time and looks like a typically worn river stone. It likes to stick to the magnet, but must be low in ferrous metal, as it is not difficult to pull it from the magnet.

I did find another smaller stone stuck to the magnet, But I lost it. I am headed back after work next week to see if there are any more.

Any thought from the pics if it could be a chondrite? 

Thank you in advance for the help!

Dave

85EF34DC-4F3C-48AC-89AE-7D7895AA9801.jpeg

349349F3-F41D-4A5B-BFE4-849044814EB9.jpeg

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lots of rocks will stick to a magnet...that does NOT appear to be a meteorite...

fred

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I have done enough magnet fishing. That is the first time I have seen a rock stick. I have never been in that part of the river.  It must be in an area with some slightly different geology. Thanks for taking the time Fred.

 

Dave

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Just my guess....you can read all about meteorite rights and wrongs at the top of this forum...

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2 hours ago, Meteorite Tester said:

It would be fairly simple to test it for nickel, then go from there.

Do you see any characteristics that would warrant a nickel test?

I was under the impression that a suspect stone should be "windowed" to get a glimpse of the interior. Then, if metal flakes or chondrules were visible a nickel test was warranted. It seems to me that nickel testing stones with no meteoritic characteristics other than slight magnetism would be a waste of time and resources.

It seems that I have been using the wrong methodology for met identification. I generally do not test for nickel unless a visual inspection of the stones interior cannot rule out the possibility of a meteorite. I was under the impression that unless you saw free metallic iron flecks in the matrix a nickel test would be rather useless.

What is your opinion on the proper steps for meteorite ID? Shouldn't the basic field tests be done before testing for nickel?

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Posted (edited)

No, I don’t, however, since the specimen has been under water, it may have been severely worn, and even the apparent layering, which is indicative of a terrestrial rock, could have been caused by the time in water, it is interesting that the specimen has a magnetic component.

a nickel test would be the easiest as a start. 

I always start with a density test first, then a microscopic inspection, looking for things that say meteorwrong, like crystals of quartz, etc. this is of coarse, after it passes the field test and makes it into the goody bag.

my field test is very simple, 

1. The specimen should not look like any other rock in the area.

2. It should obviously not be sedimentary , or have any type of layering

3. A magnet test and quick cursory look with a 10X jewelers loop is helpful.

finally, if in doubt, pack it out, you can toss it away much easier than trying to find the spot and specimen again if you should later on discover that the latest rare meteorite has the same characteristics as the rock you passed on last week.

Edited by Meteorite Tester
  • Hmmmmmm 1

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It is absolutely not a meteorite, just a piece of ironstone, very evident from the picture, there's no need for further testing.

Nickel tests are rarely, if ever, used for chondrites; they are primarily for iron meteorite identification.

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The only reason for testing for the presence of nickel is due to the magnetic characteristic of the specimen, being iron stone, as you say, would seem to require this test to be definitive 

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20 minutes ago, Meteorite Tester said:

The only reason for testing for the presence of nickel is due to the magnetic characteristic of the specimen, being iron stone, as you say, would seem to require this test to be definitive 

This specimen is mineral iron. Not free metallic iron. There is no reason to test for nickel. A window is all it takes to prove this. That provides both streak and an opportunity to peek beneath any crust or oxidation. This is foundational to field testing and will positively identify this specimen as terrestrial. A nickel test is not needed to do that.

You do not need a nickel test to differentiate between "ironstone" and free metallic iron. They are easily differentiated by their physical characteristics.

I respectfully disagree with your field testing methodology. It certainly does not mesh with what I understand to be the correct procedure.

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2 minutes ago, Meteorite Tester said:

I find that cutting a window into a suspected specimen in the field to be quite challenging

I use a piece of sandpaper glued to a stick. No problem at all.

I find nickel testing rocks that have no meteoritic characteristics challenging. 

Each to his own I suppose.

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Of coarse, I do not advocate nickel testing every single suspected specimen, but when a questionable specimen is determined to have merit for further testing, the nickel test is one of the easiest test to perform, again, only if the specimen warrants it.

as for cutting a window, I normally reserve this as prep for looking at the specimen with the microscope, in which case, I need a larger and flatter, polished surface, maybe due to my age and failing eyesight.

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7 minutes ago, Meteorite Tester said:

Of coarse, I do not advocate nickel testing every single suspected specimen, but when a questionable specimen is determined to have merit for further testing, the nickel test is one of the easiest test to perform, again, only if the specimen warrants it.

as for cutting a window, I normally reserve this as prep for looking at the specimen with the microscope, in which case, I need a larger and flatter, polished surface, maybe due to my age and failing eyesight.

You advocated nickel testing this one. Why?

And then there is this statement...

"The only reason for testing for the presence of nickel is due to the magnetic characteristic of the specimen, being iron stone, as you say, would seem to require this test to be definitive".

A meteorite hunter learns on his very first "meteor wrong" how to differentiate "ironstone" from free metallic iron. And it certainly isn't a nickel test that is definitive. This is just basic mineral ID 101.

It seems that someone is a bit confused. 

I'm certain it is me. I'm probably just getting old and forgot how to ID a meteorite. :inocent:

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I did not consider the possibility that the OP had the equipment or expertise to make the determination as you suggest, not many newbies  in the  field have your experience hence, they post and ask on this form for a positive ID  based upon a poor quality photo.

next time I will just let the visual photo experts provide advise, I have better things to do

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12 minutes ago, Meteorite Tester said:

I did not consider the possibility that the OP had the equipment or expertise to make the determination as you suggest, not many newbies  in the  field have your experience hence, they post and ask on this form for a positive ID  based upon a poor quality photo.

next time I will just let the visual photo experts provide advise, I have better things to do

Rubbing the specimen on a piece of sandpaper (or the underside of a toilet tank lid) and observing the streak and luster is how you differentiate sub-metallic mineral iron from free metallic iron. This simple observation takes no expertise or equipment and is foundational to mineral identification. It would be the next logical step if the OP wanted to investigate further. 

Nickel testing on the other hand requires equipment and expertise and would determine exactly nothing. So there is some disconnect in your logic. 

 I am asking for nothing except a discussion on your methodology. It seems you are unable or unwilling to discuss it.

For a guy who calls himself "Meteorite Tester" you would think that this discussion would be possible. :idunno:

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6 minutes ago, Meteorite Tester said:

A streak test is only definitive if the specimen is not a meteorite, as most meteorites do not leave a streak

But all earthy iron does leave a streak. So there is that.

And grinding a window shows the luster and whether it is metallic or sub metallic and this differentiates terrestrial iron from meteoritic iron in a stone. So there is that as well.

This is just basic ID my friend. 

A simple window will prove that rock is terrestrial. No, it won't prove it is a meteorite but then again that is not what a field test is intended to do.

You do realize there are about a dozen really experienced meteorite hunters here that know all this stuff like the back of their hand don't you?

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1 hour ago, Meteorite Tester said:

I do most of my work in a lab, so the test I am used to performing are definitive, I am not a dirt monkey

That sounds like an excuse followed by an insult to me.

I think you are a novice posing as a man of knowledge. We are talking basic mineral ID here and you seem to be over your head on the most fundamental concepts.

There are dozens of expert "dirt monkeys" on this forum that you could learn a whole bunch from. But you will have to stop pretending to be an expert first.

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I did not call anyone a dirt monkey, I stated that I was not one, as you so  eloquently  implied

as for expert status, I never stated that either, I just stated that I test  meteorites, where, based upon your response, you test terrestrial rocks.

I was thrilled that you were “Done with this”, premature since you obviously are not.

sorry if I am not impressed with your status, I do not impress easily.

 

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Never been impressed with nickel tests (especially since most people use something generic that just turns red if nickel=yes which tells you absolutely nothing), if something warrants that type of analysis then I go with XRF. 

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