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13th February 2005, 11:55 PM | #1 |
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Adding to what BSM said, the "fingerprint" is in the ratios of isotopes of elements. Although all planets and asteroids (and meteorites) presumably originated at the beginning of the solar system, they contain different ratios of the isotopes of various elements.
A big reason for this is that earth has a molten core kept that way by radioactivity, whereas most asteroids are too small for this process. The molten core melts material, causing isotopes to fractionate. Lavas from different volcanoes are, to some degree, recognizable from their isotopic fingerprints (there was an article on this in Science News recently, if you want an accessible source). Also, radioactivity at the core might produce breakdown products from fissioning heavy elements... To make a long story short, one can distinguish between a meteorite and a rock, simply on the basis of the isotopic fingerprint. A blade is another story. I'm just guessing that Prof. Piaskowski can't distinguish meteoric iron in Keris blades either because a) he hasn't found a genuine one yet (this is a provenance question) and/or b) the meteoric iron is mixed with terrestrial iron and/or nickel in order to form one layer of the pamor. Since the earth is definitely not uniform in isotopic signatures, mixing metals could easily hide the partially extraterrestrial origin of some blade. A purely meteoric blade would be easy to identify, but one of mixed origin would be difficult. For the whiskey and wine crowd on this board, this is analogous to the problem of identifying the parent materials in a blended whiskey or wine, based on taste. And before Nechesh asks, I'm a professional ecologist. I don't deal with metal isotopic chemistry at all, but I'm familiar with isotopes of lighter elements. Fearn |
14th February 2005, 12:23 AM | #2 |
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fearn,
You make an old Geologist proud (OK, I’m not one any more). We didn't work with isotopes unless we were dating the material. Pure chemistry was enough, generally reported in oxides for non-metallic materials, for example :FeO, SiO2, MgO, Al2O3, Na2O, K2O, P2O5 and so on. But keep in mind the time frame... isotopes were not carrying the weight if importance as they may have today (I'm old or I feel that way). nechesh, You will have to forgive me, I have been in the Paint industry for 29 year now... meteorites and tektites are just a hobby now (just a few too many hobbies). |
14th February 2005, 12:24 AM | #3 |
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Oh no!! next you'll tell me Jerry Springer is staged!!!
Just kidding. I know there isnt much reality in the media in general, I work for the airlines so I can totally relate!! I appreciate the detailed explanations on these technical studies. These topics have always been pretty intimidating, and you guys make things much more understandable. Thanks! All the best, Jim |
14th February 2005, 01:32 AM | #4 |
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Jim, i hate to tell you this, but not just Springer, professional wrestling too! When you're feeling stronger we'll have a talk about that Santa Claus guy.
Fearn, if i remember correctly, your 2nd suggestion for the difficulty in IDing meteoric material in keris is the one. If i'm not mistaken, this material must be mixed with terrestrial iron inorder to make use of it. |
14th February 2005, 11:52 AM | #5 |
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This is what made me start the topic:
Arms and Jewellery of the Indian Mughuls, Lahor 1947, written by Abdul Aziz. In the book he tells about Shah Jahangir, and about a falling meteor. The meteor fell around 10 April 1621 close to a village called Jalandhar. The meteor was dug up and presented to Shah Jahangir: I ordered Master (Ustad) Daud to make a sword, a dagger and a knife out of it, and bring them to me. He represented that it would not stand below the hammer, and fell too pieces. I told him in that case to mix it with other iron and make use of it. As I had told him, he mixed three parts of lightening-iron and one of other iron, and having made two swords, one dagger, and one knife, brought them to me. From the mixing of other iron he had brought out its quality (watering). According to the manner of the excellent swords of Yaman and [the swords of] the South, it could be bent, and became straight again. I ordered him to test it in my presence. It cut very well, equal to true swords. What Shah Jahangir means by saying 'a true sword' I don't know, but it is clear that meteoric iron had to be mixed, at least with the knowledge they had at the time. So fearn, here we have a problem, as it seems as if you won't find a pure meteoric blade. From you posts, like with the posts of others, I more and more got the feeling, that you knew much more about the subject than most of us. Thank you for taking your time to explain it to us - so far in a language which most of us can follow . Nechesh, the above should answer your question as well. Jens |
14th February 2005, 05:31 PM | #6 |
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Hi Jens,
The event you are citing from the Aziz book is descibed almost verbatum in Pant (p.218), with the combining of three parts 'lightning iron' as the meteoric material is termed and one of other iron. In the original post you noted that meteoric iron is discussed in other references in edged weapons blades, especially the keris, but not incidents or applications from India. In Pant, (p.218) he notes. "...no special study of weapons made of meteoric iron has been made in India so far. However a sword at present in the Alwar Museum, Alwar (Rajasthan) is said to have been made of meteoric iron". He also notes that in one of the early dealers here in the U.S. catalog, Robert Abels (Catalog #32, p.87, #700) there is an Indian sword with 21" meteoric blade. Despite the obvious scepticism, it would be interesting to see if these swords actually did have such blades. The one in the catalog obviously is long gone, Abels was dealing in the 60's and 70's, but possibly the museum example is still there. A note concerning aesthetics : from Stone (p.664) "...the most brilliant watering is in Malayan blades made by piling alternate layers of mild steel and an alloy of iron and nickel containing about 3% nickel. These are welded and twisted in various ways and then etched with a mixture of lime jiuc and arsenous acid". "..in the old blades the nickel alloy was meteoric iron, in some of the later ones it was Krupps nickel steel". This it seems the nickel was one key ingredient for the pamor, and if the appearance was 'meteoric'..all the better. Since nickel is an earthly element it does seem it would be difficult to differentiate between the earthly matter and extraterrestrial. Question: are there unidentified elements or minerals found only in extraterrestrial material, such as the rocks from mars or the moon? Best regards, Jim Last edited by Jim McDougall; 14th February 2005 at 05:43 PM. |
14th February 2005, 05:54 PM | #7 |
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Hi Jim,
We have, in some of the earlier posts heard about how difficult it is to recognise meteoric iron, especially if it is mixed, so how Pant could come with a statement like that, about a blade he has never seen, I don’t know. Maybe the museum in Alwar has such a sword, but here too the metal for the blade would be mixed. Should the museum have the sword, it is a question if they would let it be tested. I know of the Pant book you quote from, but I don’t have it, so I did not know what he wrote on the subject. Jens |
14th February 2005, 07:48 PM | #8 |
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Hi Jens,
You are right, the statements and comments that Pant has presented concerning the study of meteoric iron in India are simply presented as a point of reference, not necessarily conclusive. It would be difficult for him to prove that absolutely no study of any kind has been made on this topic in India, however we would presume that such published material was limited as not readily found. Therefore, the subject of meteoric iron in India is clearly not much discussed. As for the swords he has cited, the one in the museum he is apparantly relaying the caption with the weapon in the museum. ...we could only hope the weapon has some sort of provenance or historical data that would explain the 'meteoric' label. As for the item listed in the Abels catalog, I would hardly consider a sales catalog used for reference in an academic discussion so again, that was simply an example cited which would just as well have been left out it just seemed interesting to note. Best regards, Jim |
14th February 2005, 07:39 PM | #9 | |
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Quote:
You will find there are no "unearthly" elements in meteorites. What sets them appart is the "chemical mix" in which they were formed (and the physical conditions of formation as well). If you were to see a meteorite sitting on the ground for any time at all, you may very well pass it up as a common rock (I am including all meteorite types). As you may have noticed that all of the meteorites mentioned in this thread that were used as sword making material, were witnessed falls. The cosmic connection was made becaused of an observed event. If they had not been observed, even if some kind of crater forming event occured... I think someone would have scrached their head and not reconize the interesting stones laying there as being from above. I believe this is apart of the issue at hand. By simple observation, how do we tell if a Keris or sword contains meteoric iron. For me, I do not need meteoric iron to make a cosmic connection, take a look around you... everything you see, the elements that make us and everything around us were forged in a star. I have seen some of the Gibeon meteorites that had simply been hammered into shape to make a spear... and when polished and acid etched, still showed the Widmanstatten structure, meaning it had not been forged or heated to any large degree or it would have destroyed this internal crystal structure. I am not an expert... so correct me if I am wrong, it maybe that the finer crystal structural octahedrites (vs. medium and coarse) may be more malleable (Gibeon is a fine octahedrite type IVA)? If the meteorite in India would not stand below the hammer, and fell too pieces, then it was the "luck of the fall" or is it draw? |
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