It needs equipment to test and find a related organization to see if they want to test it for you for free.
Dear Frieda Mah
About meteorites, an experience expert can use his/ her eyes to identify them through the characteristic. Equipment test is the last step.
I must make sure it has 50% possibility; I can bother a related organization. Now I am look for some information from RG scientists.
Dear Chun Liu,
from what I can see on these pictures, this is definitely no meteorite. I can see no fusion crust, no regmaglypts, nothing at all. This pebble seems to show a very thin weathering crust and it seems to be a fine-grained sandstone or a granite, this can only be veryfied by preparing thin sections.
All the best,
Elmar
Dear Paola
About tiny shining silver light metals, my personal view, are still metals, not crystal facets. I post the picture of another same sample with some silver light metals. The metals are bigger and more than the metals in the above samples. Its texture is same as brick. It is magnetic. The metals don’t rust in the air.
Dear Paola
My personal experience, the good way to separate the tiny shining silver materials which is metal or crystal facet is using light. Crystal face only reflects direct strong light. In room which doesn’t bright it doesn’t shine. But tiny metals still shine in the room.
Dear Chun Liu,
it seems to me that you might have the impression that people do not grant you the finding of a meteorite but believe me, this is not the case. Paola is completly right, this is not a meteorite!!! There are no regmaglypts, no fusion crust, no metal, nothing at all. And even if it is metal, there are so many types of rocks (artifical or natural) containing a metal Portion.
I have seen hundreds (or even thousands) of meteorites and I have also seen hundreds of pseudo-meteorites. I get one sample each week in avarage in order to analyze it on a possible meteoritic origin and 99.9% are no meteorites. But most samples I got are much closer to meteorites than your sample. I repeat: this sample does not fulfill just a single optical criteria for a meteorite.
Still believing it could be a meteorite is wishfull thinking and you are just wasting time.
All the best,
Elmar
Dear Elmar Buchner
Thank you for your reply. I haven’t doubted you experience and knowledge on the science.
And I also don’t confirm these are meteorites. Because the External feature of these specimens - high temperature and metal compositions, so I think there are maybe meteorite in these samples. I just give the evidence I have observed to support my thought.
The sample contains a lot of silver shining metals. The metal content is more than 5%. And the metals are magnetic metals, so Fe and Ni are two of the main metals. It is one of the criteria for a meteorite. About optical criteria, it has weathered heavily, so no regmaglypts, no fusion crust.
Dear Paola
“Even if you find magnetic metal, this does not imply that you have Ni content in it.”
I don’t agree your view.
First, look at the periodic table of chemical element which includes all chemical elements our human known, not except the elements in meteorite. There are three magnetic metals (Fe, Co, and Ni) in the table. Only two magnetic metals shine silver light Fe and Ni. Fe easily rusts in the nature atmosphere, especially in acid rain circumstance. If the magnetic metals don’t rust for long history, what they can be? My personal opinion, the metals are Ni or ally of Fe and Ni.
I know you are familiar with the knowledge.
Dear Paola
“Among the samples you posted one seems to be burned and this could have archeological implication maybe, if you are investigating on a furnace site, for example (?). But burned is not melted. ”
About the view point, I also don’t agree you.
15 years ago, my friends and I wanted to do some artwork with pottery clay. So we have studied some kind of unglazed earthenware. The Sintering temperature of ceramics is more than 800℃.
But pottery clay doesn’t melt wholly in the so high temperature. Some meteorites also like that.
If you have seen refractory brick, you will understand.
Dear Chun Liu,
That these samples have a metallic portion does not mean anything and magnetic metal does not necessarly mean that it has a Ni content. Did you check this at least by SEM-EDS? Why not haematite or magnetite??? Fe oxides are so common in many types of rocks.
If you assume that it is a stony-iron meteorite, this type of meteorites comprise pallasites and mesosiderites. Did you detect any olivine, pyroxene or chromite or any other mineral typical for meteorites? And if it should be Fe-Ni metal, is it kamacite, taenite, or tertataenite?
It is not sufficent to identify a meteorite by the fact that there is some rock with 5% magnetic metal. Once again, this is wishful thinking, but it`s up to you...
All the best
Elmar
Dear Elmar Buchner
Thank you for the chance that you give me to discuss with you on the problem.
“That these samples have a metallic portion does not mean anything and magnetic metal does not necessarly mean that it has Ni content. Did you check this at least by SEM-EDS? Why not haematite or magnetite??? Fe oxides are so common in many types of rocks. “
Magnetite is black or indigo-blue in color, and its streak is also black. It has a metallic to dull luster.
Hematite is a component of rust but magnetite is not. It can be red, brown, reddish brown, back or silvery color.
From the sample’s color, it contains Fe2O3.but Fe2O3 is not magnetic. It doesn’t have magnetite in it. The magnetic feature of the sample is from the silver shining metals. The probability that the silver shining metals contain native Ni or alloy of Fe and Ni is very high.
By the way, about XPS，EDS I also wish it can be checked.
Thank you again
LIU
Dear Liu,
o.k., you wish to discuss to everybody is convinced: yes it's a meteorite!
But back to the facts: haematite can be slightly magnetic and magnetite can be black, blueish, silver or anything else. It is negligent to classify a mineral by it's colour, but it's even worth to conclude on Ni content by the colour of a mineral or metal alloy.
So many minerals exist that are magnetic and may appear silver-grey in colour, one example amongst many others is molybdenite.
And even if this metal should be an Fe-Ni alloy (most probably it is not), the samples you showed do not fulfill any criteria for meteorites!
Best,
Elmar
Dear Elmar
We are discussing how to observe a meteorite with unaided eye. We are discussing a possibility and the common methods with unaided eye.
“So many minerals exist that are magnetic and may appear silver-grey in colour, one example amongst many others is molybdenite. ”
Yes, I have found a lot of minerals which appear silver-grey in colour are magnetic. But my samples above are not silver-grey in colour.
Yes, heated hematite is magnetic.
No mineral contains Ni and Fe or Ni more than 5%. If the silver shining metals are more than 5% Ni or Ni and Fe, why the samples have not fulfilled any criteria for meteorites
Thanks
Liu
Dear Elmar
“If you assume that it is a stony-iron meteorite, this type of meteorites comprise pallasites and mesosiderites. ”
About the problem, I will pay more my attention on looking for about information.
At same time I add another sample with a lot of silver shining metals.
Thanks
Liu
Dear Liu,
how many samples of pseudometeorites do you have, you constantly present a new one...
The latter sample seems to be a granite and the "metallic portion" strongly resembles muscovite!!
I have the impression you are kidding me, therefore, this is my last response...
Cheers
Elmar
Dear Elmar
I am a collector of meteorite for 15 years. I exchange meteorites with other collectors sometimes, so the kind of samples I still have a few. I am not kidding any one here. I think all samples maybe belong to one meteorite shower. So the specimens are worth to study.
I add a new one.
Dear Chun I agree with the others that the sample photograph as given does not indicate a fusion crust. I have worked quite a bit on meteorites including the fusion crust of the same. One can prepare a thin section and see the presence of chondrules, as in case of chondrites while there are other characteristic features in achondrites as well iron group of meteorites.
Dear Debashish Sengupta
Thank you for your reply.
First not all meteorites have clear fusion crust. And a lot of meteorites’ fusion crusts have been weathered before finding. The fusion crust (yellow surface) of this one still has some left.
By the way, the one was found in yellow sand.
Earthenware is glazed or unglazed nonvitreous pottery which has normally been fired below 1200°C. Earthenware comprises "all primitive pottery whatever the color, all terra-cottas, most building bricks, nearly all European pottery up to the seventeenth century, most of the wares of Egypt, Persia and the near East; Greek, Roman and Mediterranean, and some of the Chinese; and the fine earthenware which forms the greater part of our tableware today. Generally, earthenware bodies exhibit higher plasticity than most whiteware bodies and hence are easier to shape by RAM press, roller-head or potter's wheel than bone china or porcelain. Due to its porosity, earthenware, with a water absorption of 5-8%, must be glazed to be watertight. Earthenware has lower mechanical strength than bone china, porcelain or stoneware, and consequently articles are commonly made in thicker cross-section, although they are still more easily chipped.
https://en.wikipedia.org/wiki/Earthenware
Dear all
“The latter sample seems to be a granite and the "metallic portion" strongly resembles muscovite!!”
The picture posted above is not clear, so I add another one. Enlarging the picture the shining metals is clear. Some shining metals are circled with light yellow light. I think the metals maybe Ag. Ag is diamagnetism. So the sample is not magnetic.
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