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Help with this rock-Nepfrite?

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Ivigo, If I were you, and was this intrigued by this rock, I would have it taken or sent somewhere for testing. That will be the only real way to satisfy your curiosity.

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16 hours ago, fuss said:

Ivigo, If I were you, and was this intrigued by this rock, I would have it taken or sent somewhere for testing. That will be the only real way to satisfy your curiosity.

Yes i know, i have communication with an expert in Athens but at the moment is close for coronovirus.

I found one very similar meteorite ....

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6208157/

SUMMARY

 Ungrouped achondrite NWA 7325 is a protogranular to poikilitic-textured assemblage of 10–15 vol. % Mg-rich olivine (Fo 98), 25–30 vol. % diopside (Wo 45, Mg# 98), 55–60 vol. % Ca-rich plagioclase (An 90), and trace amounts of Cr-rich sulfide and Fe,Ni metal. In terms of modal mineralogy and mineral compositions it is unique compared with all known meteoritic materials other than a rare feldspathic lithology found as clasts (“the magnesian anorthitic lithology”) in polymict ureilites. In agreement with previous investigations, we interpret NWA 7325 to be a cumulate rock that crystallized at temperatures ≥1200 °C and conditions of very low oxygen fugacity from a generally basaltic, incompatible element-depleted melt. Trace element abundances in plagioclase indicate that this melt could only have formed by fractional (not batch) melting of a chondritic source, or a multi-stage igneous history. NWA 7325 experienced a subsequent event (argued to be impact and excavation), in which plagioclase was substantially remelted and recrystallized with a distinct texture.

mercury-meteorite_custom-e695ca3de2a1f3167e3cd746f6171402c280a83b-s800-c85.jpg

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https://en.wikipedia.org/wiki/Meteorite_shock_stage

Shock grade

The fracturing of crystals and other features must be observed under a microscope with shock effects observed under polarized light. Larger structures, such as shock veins, are visible to the eye. Many of the shocked veins formed at the boundaries of polished surfaces of brecciated specimens exhibit intricate spider-web-like structures. Following is a summary of the shock grades:[3]

  • S1: completely unshocked (up to 5 GPa)
  • S2: very weakly shocked (5-10 GPa); uneven darkening of olivine as seen under polarized light; planar and irregular fractures (breaks in other than a natural cleavage plane.)
  • S3: weakly shocked (15-20 GPa); weak fractures in olivine seen under polarized light; dark shock veins and some melt pockets
  • S4: moderately shocked; (30-35 GPa); weak planar fracturing of olivine under polarized light; some pockets of melted material, dark interconnected shock veins
  • S5: strongly shocked (45-55 GPa); very strong planar fracturing and deformation features in olivine; alteration of plagioclase into maskelynite; formation of dark melt veins
  • S6: very strongly shocked (75-90 GPa); olivine recrystallizes, with local alteration to a mineral called ringwoodite and shock melting of plagioclase to a glass

https://en.wikipedia.org/wiki/Meteorite_shock_stage#/media/File:Impact_pseudotachylite,_Rochechouart_Impact_Crater_west-central_France.jpg

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Posted (edited)

Ivigo,  the other members comments are correct.  What you have is a metamorphic rock which has been fractured (broken into pieces) then the fractures filled in with green colored quartz, most likely chalcedony, a micro-crystalline quartz and very common. 

It definitely is not a meteorite; yes, I have studied meteorite classifications back in collage and know what to look for.

Edited by 4meter
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Posted (edited)
1 hour ago, 4meter said:

Ivigo,  the other members comments are correct.  What you have is a metamorphic rock which has been fractured (broken into pieces) then the fractures filled in with green colored quartz, most likely chalcedony, a micro-crystalline quartz and very common. 

It definitely is not a meteorite; yes, I have studied meteorite classifications back in collage and know what to look for.

Hi, i am not against you or the other member and of curse i am not sure if this rock is a meteorite. But i am sure for the impact crush and i am not sure if this material is quartz. The knife scratch it. All the material and not only the amorphous and melting. Maybe some place in the rock is more hardness from other .

Also all the rock  is pale greenish , from light green to very dark green. The strange is have too many iron and not only this but also is magnetic. Not too much but magnetic.

The streak color is light green to gray. I don't know any iron mineral in green color and magnetic.

I will try many days to found any information about green minerals with iron and magnetic and with 4,5-5,5 hardness. It also generally does not scratch the glass, except for some parts that, as I said, are harder and they scratch it, but not easy.

Also the green colored quartz you say is not only inside the fractured as you say but also inside to the rock if you see the photo.

Maybe is not iron only, but nickel and cobalt.

 

Edited by ivigo

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3 hours ago, 4meter said:

, I have studied meteorite classifications back in collage and know what to look for.

:inocent:

:tisk-tisk::rasberry:

Did you make a collage of pictures of meteorites- in college?

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3 hours ago, ivigo said:

Hi, i am not against you or the other member and of curse i am not sure if this rock is a meteorite. But i am sure for the impact crush and i am not sure if this material is quartz. The knife scratch it. All the material and not only the amorphous and melting. Maybe some place in the rock is more hardness from other .

Also all the rock  is pale greenish , from light green to very dark green. The strange is have too many iron and not only this but also is magnetic. Not too much but magnetic.

The streak color is light green to gray. I don't know any iron mineral in green color and magnetic.

I will try many days to found any information about green minerals with iron and magnetic and with 4,5-5,5 hardness. It also generally does not scratch the glass, except for some parts that, as I said, are harder and they scratch it, but not easy.

Also the green colored quartz you say is not only inside the fractured as you say but also inside to the rock if you see the photo.

Maybe is not iron only, but nickel and cobalt.

 

You don't have a mineral. You have a rock. Rocks are made of minerals. 

Minerals can be identified by streak. Rocks not so much. You are getting the combined streak of many minerals.

Your iron in the rock is mineral iron. Not free metallic iron. Therefore it is an terrestrial rock and not a meteorite.

Sad but true. 

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2 hours ago, Stillweaver hillbelli said:

:inocent:

:tisk-tisk::rasberry:

Did you make a collage of pictures of meteorites- in college?

LOL!   the fingers are faster than the eyes, brain, attention span, etc, ect, ect.....:wee:

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On 5/9/2020 at 11:55 PM, ivigo said:

Yes i know, i have communication with an expert in Athens but at the moment is close for coronovirus.

I found one very similar meteorite ....

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6208157/

SUMMARY

 Ungrouped achondrite NWA 7325 is a protogranular to poikilitic-textured assemblage of 10–15 vol. % Mg-rich olivine (Fo 98), 25–30 vol. % diopside (Wo 45, Mg# 98), 55–60 vol. % Ca-rich plagioclase (An 90), and trace amounts of Cr-rich sulfide and Fe,Ni metal. In terms of modal mineralogy and mineral compositions it is unique compared with all known meteoritic materials other than a rare feldspathic lithology found as clasts (“the magnesian anorthitic lithology”) in polymict ureilites. In agreement with previous investigations, we interpret NWA 7325 to be a cumulate rock that crystallized at temperatures ≥1200 °C and conditions of very low oxygen fugacity from a generally basaltic, incompatible element-depleted melt. Trace element abundances in plagioclase indicate that this melt could only have formed by fractional (not batch) melting of a chondritic source, or a multi-stage igneous history. NWA 7325 experienced a subsequent event (argued to be impact and excavation), in which plagioclase was substantially remelted and recrystallized with a distinct texture.

mercury-meteorite_custom-e695ca3de2a1f3167e3cd746f6171402c280a83b-s800-c85.jpg

Looks like Nepfrite  . . . Sp.

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Posted (edited)
2 hours ago, Bedrock Bob said:

You don't have a mineral. You have a rock. Rocks are made of minerals. 

Minerals can be identified by streak. Rocks not so much. You are getting the combined streak of many minerals.

Your iron in the rock is mineral iron. Not free metallic iron. Therefore it is an terrestrial rock and not a meteorite.

Sad but true. 

Hi Bob, maybe you have right ,for sure is not only one mineral,  but now after melting the rock looks different.  They have found some unusual  meteorite rich in iron, nickel  without metallic iron or nickel. I post one here(some posts before). And is not only this one.

S6: very strongly shocked (75-90 GPa); olivine recrystallizes, with local alteration to a mineral called ringwoodite and shock melting of plagioclase to a glass

ringwoodite have iron .

Edited by ivigo

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14 minutes ago, BMc said:

Looks like Nepfrite  . . . Sp.

Yes and have no metallic iron and nickel. 

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19 hours ago, Bedrock Bob said:

OK...

:idunno:

Hi Bob, i didn't  say you are wrong but all meteorite is not iron or iron stone only. This is the exiting in all this. Out there is meteorite from mars , maybe from Aphrodite, Mercury and other places.  Basaltic and unusual rock. You never know ....but to be sure need examinations.  You never know.....

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Posted (edited)

As continue to be curious about my rock still waiting to send them in lab for examination I study it again and again.

I have a pocket hand microscope and I carefully examined the inside on the broken side at 60x analysis (have a problem and i fix it yesterday).

The band is, is not possible to take photos ,etc.

So, i found in many places in the rock Planar deformation features, or PDFs in different directions but always parallel to each other and looks glassy.

When the green mineral (crystal) is almost flat and clear without other minerals  is very easy to see PDFs clear without any doubt or what is. .

In my rock the PDFs looks more closer to the second photo , same parallel lines in different directions.

Also i found dark mineral in needle shape in many places, sometimes individually but also in masses. Some of them is inside to green mineral. But the most of them is out, inside in the other darkest minerals in the rock.

So, any idea?

The pdfs in my rock looks like this in photo but my analysis is not so big. For sure is good this but need examination i know.

pdfs.jpg

820qtz.jpg

Edited by ivigo

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Your PDFs are just the cleavage striations on the plagioclase feldspar fragment within the sample and the needle shaped minerals could be any number of minerals which develop under various metamorphic temperature/pressure conditions.  Again, all evidence shows your sample to be a fractured, metamorphic rock.

To see "shocked quartz" features that a diagnostic of a meteorite strike; that is the slight deformation of the country rock and tale, tale shearing (shocking) of the quartz grains within the host rock, you need more than 60X; you need an electron-microscope.  One usually looks for "cone in cone" type mega-features in the host rock, during field work that is supported by evidence shock quartz seen under lab conditions to identify a meteorite strike.

The bottom picture looks like a view in polarized light with cross analyzers.  How did you get that picture?

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First i will begin with all here they say again and again , no quartz in meteorite.

So here we are. https://www.sciencedaily.com/releases/2018/08/180822091025.htm

Second, the PDFs is not only up to terrestrial rocks in the impact  crater but also in meteorite. 

So here we are: https://onlinelibrary.wiley.com/doi/abs/10.1111/maps.13367

Third, in my rock the PDFs is only up to the melted amorphous green mineral. 

Also, you can see it with optical microscope but is better to be sure the use of electron microscope with polarized light.

My picture is not mine but is similar to how they looks (PDFs in my rock) . Nothing is sure before the right examination.

Thank you

 

 

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