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21st June 2010, 02:03 AM | #31 |
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G'day Rasdan.
Mate, I cannot tell one thing from the other when I look at pictures. Even when we know, or strongly believe that the material is the same, its appearance can vary enormously depending on the way it has been worked, the amount of surface erosion, and the staining. Anybody who reckons he can tell much from pictures of pamor, or iron, is just kidding himself. To really see the nature of the material you need to hold it in your hand, feel the material, and turn it this way and that in good light. Then you might --- only might --- get some sort of indication as to what you're looking at. Why is meteoritic material often prickly to the touch? No idea. How do we differentiate an old iron that is folded numerous times to make a dense material and modern iron which is already dense? It looks different. How does it look different? I cannot explain, but it has a different look.Yes, you can mostly see some sort of grain in it, even when it is very padat you can see grain under magnification. How can we differentiate the lines of fibrous inclusions found naturally in wrought iron to the folding lines produced by repeated folding or mbesut process? It looks different. Again I cannot explain, it just looks different. Something to bear in mind:- prior to about 1850 steel was not mass produced, and even after mass production began, it was only common in major areas of population in industrial countries. Up until WWII wrought iron was a pretty common material. About 1950 mass production of steel became very economic and efficient with the introduction of the basic oxygen process, since that time mild steel has replaced wrought iron completely. Thus, in a modern, current era blade we could expect to see mild steel rather than wrought iron, but in anything from pre-WWII we would be much more likely to see wrought iron. Go back into the 19th century and earlier, and we will certainly be looking at wrought iron. Up to now this thread has been about just pamor. Here is the original question:- I would greatly appreciate if anyone could post images contrasting the differences between the pamors - meteorite, luwu, and modern nickel. I posted examples of recent blades with various types of pamor. None of those blades are more than 150 years old, and most are much younger than that. In other words, this was all about as easy as it gets. But to be honest, if somebody else had put those examples up, and I had no personal knowledge of the blades, I could not have said with any certainty what it was that I was looking at. That was my purpose in posting the examples:- to try to demonstrate how absolutely futile it is to try to learn about pamor and blade materials from pictures. Quite simply it is totally impossible. However, when we broaden the area under consideration a bit, and we begin to enter into aspects of blade appraisal and classification, we then need to consider the entire blade, not just the pamor. When the entire blade comes under consideration we get a lot more feedback from what we can see, and all this information cross matches to assist in the appraisal or classification. Thus, if we are considering a blade that is obviously very old, there is no possibility that mild steel is involved, similarly, European nickel will not be present. We then need to decide if we are looking at Luwu material, or phosphoric iron, or one of the multitude of other materials that have been used as pamor, such as imported Chinese tools. When we get involved in this sort of exercise it gets hard. Very hard. And far, far beyond what can be conveyed by any sort of image. |
21st June 2010, 06:16 PM | #32 |
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Thank you for your explanation Alan. Do you think it is reasonable for beginners like me to forget about pamor material at the moment and try to understand iron and steel first? The problem with this approach is that some keris have very large coverage of pamor material and it becomes very hard to see the iron. My further questions are (these are the last ones as this had strayed out of topic..sorry):
1. What i understand from Wikipedia is that wrought iron is iron with low carbon content. This means that mined iron sand that were melted and cleaned can be considered as wrought iron. Is there any way to differentiate wrought iron that comes from industrial smelters and the ones that were traditionally melted and cleaned? Is it the impurities? What exactly do we have to look for in identifying this? 2. Does pig iron (http://en.wikipedia.org/wiki/Pig_iron) with 3-4% carbon qualifies as baja in keris? Had it been used (or is it possible to be used) as keris material at all? Can it be used to make kelengan keris? 3. If we heat iron with coke and we get baja (if the above is true) i have yet to see any baja that have fibrous inclusions. I had seen baja with lots of impurities, but no inclusions. Why is this so Alan? I am sure that the process is more complicated that what ever perception that i have in mind, but i have yet been exposed to any of these matters. Sorry about my ignorance Alan. Thanks. |
22nd June 2010, 01:23 AM | #33 |
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The product of a smelt is called pig iron.
Pig iron has a very high carbon content that makes it very difficult to work, so it is refined into wrought iron. The word "wrought" means worked. There are and have been various methods used to turn pig iron into wrought iron. Wrought iron has a very low carbon content, the more it has been refined, the lower the carbon content, the higher the weld temperature, and the easier to weld and to work. Theoretically mild steel can have a similar carbon content to some types of wrought iron, but in practice good wrought iron has a much higher weld temperature than mild steel, which indicates a much lower carbon content. Wrought iron has a fibrous appearance that is contributed to by inclusions of slag; during the refining and cleaning processes slag is broken up and removed along with excess carbon. Iron can be turned into steel by the addition of carbon. When the carbon is only added to the outside layers of the iron we call this "case hardening", and it is not at all the same as incorporating carbon into the iron and making it an alloy. All wrought iron will show a fibrous texture after it has been worked, but to see this texture it is necessary to etch the surface, and sometimes to use magnification. If we have not seen fibrous inclusions & etc, it is because we have not used the techniques and skills of metallurgical investigation an analysis. Rasdan, some of the information you are seeking is really within the sphere of metallurgical analysis. You're moving away from the very simple visual examination that keris fanciers use. I've tried to give a simple, brief outline of the area you're moving into, but if you wish to learn more, you are going to need to carry out study specific to metallurgy. Forget about keris in this context until you get some foundation in metallurgy. I have the results of many analyses of old keris and tombak blades that were carried out by Professor Jerzy Piaskowski of Poland. These give a very good guide to the actual content of old Javanese blade material.In fact, in some old Javanese blades, wootz was used. |
22nd June 2010, 02:39 AM | #34 |
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Concerning the matter of Wootz; was the pattern retained or lost in the process of making a keris .
As I understand it Wootz must be worked at low temps to retain the distinctive pattern . |
22nd June 2010, 03:36 AM | #35 |
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Where Jerzy found wootz it had been used for a gonjo, and the pattern was still present.
However, there is a very rare type of "pamor" that I have only seen a few times, and it bears all the characteristics of wootz. These blades were, of course, not submitted to metallurgical analysis, but bearing in mind the fact that such analysis has revealed the use of wootz in Javanese blades, I believe it is reasonable to accept that in a case where a Javanese blade looks like wootz, it very probably is wootz. |
22nd June 2010, 05:33 PM | #36 |
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Ok Alan. Thanks for you explanation. I'm having such a hard time sorting out different types of iron that had been used particularly in Peninsular kelengan keris. Since traditional references are very limited, i think metallurgy is the answer in determining quality of these kerises. Again, thank you for your help.
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23rd June 2010, 12:59 AM | #37 |
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Rasdan, in my opinion you are chasing ghosts if you are trying to identify and classify the various types of iron that are listed in old handbooks. In the lists I have there are many, many types listed, along with extremely subjective descriptions. The appearance of iron depends on a number of factors, such as the amount and intensity of forging and welding, the degree of erosion, the type and condition of the etch, the type and condition of the stain --- and so on.
To take an old, nondescript blade in less than pristine condition, and then attempt to classify that iron in accordance with the descriptions found in the handbooks is almost a totally futile pursuit. You certainly need to be able to identify high quality, dense iron, and to gauge the degree of porosity in iron, but to go further than this is to a large degree only self deception. Forget trying to name the material and concentrate on gaining skill in identifying quality and identifying rubbish. This opinion is my own opinion, and I have no intention of forcing it on others, nor of arguing in its defence. Everybody can believe what they will. However, I, and anybody else with a degree of skill in forge work and etching and staining ferric materials, can demonstrate just how easy it is to change the visual appearance of iron. Metallurgy can provide analyses and a metallurgist who is trained in historical metallurgy can tell quite a lot about material with laboratory techniques, but that does not advance the cause of a collector or student of the keris who needs to be able to look at a blade, often in very unfavourable conditions, and make a judgement as to how much money he is prepared to pay for it.For this we need to be able to look at a blade and gauge the quality of the material in the blade. In the most simple of terms, this comes down to dense, well packed material, no porosity, no forging cracks indicating hot shortness, which in turn will indicate inadequate washing, and the potential for porosity with erosion.Blades are not always in good stain, so colour is not always useful, and you really don't know what the correct colour is until you do the stain yourself, or have it done by a competent professional.Again, there is no substitute for hands on experience. |
23rd June 2010, 06:41 AM | #38 |
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I am busy taking notes ... excellent follow-up, Rasdan and Mr. Maisey
Last edited by Neo; 23rd June 2010 at 07:00 AM. |
23rd June 2010, 07:07 AM | #39 |
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Alan, thank you very much for the free lesson on metallurgy, and thanks Rasdan for addressing this "pig iron" phenomenon.
However, I feel I dont quite gauge what Alan had said. It is or it is not suitable for "pig iron" to be made baja slorok or be made keris keleng? |
23rd June 2010, 09:01 AM | #40 |
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Iron sands or other raw source of iron is smelted and the product of that smelt is pig iron.
Pig iron is refined and becomes wrought iron. Wrought iron contains varying quantities of carbon. In its raw state it contains too much carbon to be useful, so we reduce the carbon by washing the iron, and getting rid of the other impurities as well, like slag, what we finish up with is wrought iron with a very low carbon content, but we can then add carbon to this low carbon content iron and turn it into steel Wrought iron can be carburised to become steel, but the carburisation process only produces small quantities of steel. The lamination of carburised iron (steel) and wrought iron provided a tough material that held an edge :- ie, "mechanical damascus". So:- iron bearing raw material > smelt > pig iron > wrought iron > steel There is a lot of information on iron and steel technology published on the net. Heaps of stuff. If you have an interest in this all you need to do is use google. You could start with this article:- http://www.new.dli.ernet.in/rawdatau...005afb_353.pdf |
13th September 2010, 07:54 PM | #41 |
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Classic?
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