Magnetic weapons

Jens Nordlunde · 13th February 2005, 10:47 AM

Hi all,

Not all magnetite can become lodestone, it takes a special crystal structure, see what Dr. Peter Wasilewski, of NASA's Goddard Space Flight Centre, writes here http://www.phy6.org/earthmag/lodeston.htm this will answer some of the questions asked.

Fearn, I am nor a specialist on this, but I would think, that if you fold a blade many times, it will loose magnetism. I agree with you, I also think the magnetism on blades was made later – but why?
If we believe in what Dr. Peter Wasilewski writes, the lightening together with a good portion of superstition would lead them to believe that the Gods had made this metal.
I don’t know if lodestone was ever used for weapons, maybe it was too difficult to get the iron out of the stone, or maybe the percentage of iron was too small, I don’t know – but one thing it could do, and that was making other iron weapons magnetic. If they believed that the Gods gave them this stone, they would also believe in, that using this stone to magnetize a blade would give the user more power.

Nechesh, I know you did not advocating for magnetizing blades. I clean my blade and etch them, but I don’t magnetise them. The reason for this is that I don’t know if the blade was magnetised from the start, that is why I leave it be.

Rivkin, it seems as if Dr. Peter Wasilewski does not agree with you about the magnetic felt of the earth when it comes to lodestone, maybe the magnetic felt could influence ancient pottery, I don’t know, and I don’t know the reason for this.
I think you are right, that if any magnetism would be recovered in a blade after heating, it must cooled very slowly – just like the Indians did with wootz.
The defects in crystalline structures, what other metal the iron was mixed with, even in very small doses must have been a problem for the smiths, as this would have affected the way the iron should be treated. It seems to me, that wootz from one ore might have needed a slightly different treatment than wootz from another ore, according to how the iron was mixed. But I never saw anywhere that the wootz ores were magnetic, only the lodestone.

Robert, on the first link I gave, it somewhere say, that if you take a big nail which is not magnetised and hammer on one end for 50 times, the nail is magnetic – if you turn the nail and do the same on the other en of the nail, you will change the poles.

Jim, I think a crude compass was made much earlier than about 11th century AD, try to read this:
For many years magnetism was just a curious natural phenomenon and its only use was in navigation as what we now refer to as the mariner's compass and which was probably first developed by the Chinese some 4500 years ago. The earliest mariner's compass comprised a splinter of loadstone carefully floated on the surface tension of water.
You can find the whole text here http://www.newi.ac.uk/BUCKLEYC/magnet.htm if you are surprised when reading this, I understand you – I was surprised too.

Does anyone know if lodestone alone, or in combination with iron/wootz was used for making weapon?

Interesting questions you ask – but you must remember that I am not an expert – I try to learn as fast as you ask the questions.

yannis, interesting what you write to Jim, try to have a look on the link I gave him.
Yes, filing on a blade can make it magnetic, but you would have to file in the same direction the whole time - not back and forth, and I think it would be an advantage if the file was magnetic. I doubt however if it would make a kard blade as magnetic as the one you have, but I don't know it.

Jens

Rivkin · 13th February 2005, 05:26 PM

I believe that the case with Wasilevski is that his message have been probably perverted by "popular" explanation - probably what he meant is that extremely well magnetized samples have origins different from just being cooled in Earth magnetic field.

Concerning the knowledge that ancient iron (whether in pottery, iron deposits or special spherical boxes lying on the ocean's floor) is magnetized alongside the Earth magnetic field at the time of the iron sample's cooling period is a well known fact, avoiding "real" papers I would bring your attention to:
http://www.sciencetech.technomuses.c...fo_Magnets.cfm

"Magnetite is magnetic because its molecular structure has allowed it to retain the alignment of particles caused by the Earth's magnetic field during its formation millions of years ago. When heated to high temperatures magnetite loses its natural magnetism. "
http://www.tufts.edu/as/wright_cente...xt_plan_5.html
"Finally, a fourth bit of evidence also favors the idea of plate tectonics, although here the data aren’t as robust, their implications not as clear. This evidence is supplied by paleomagnetism—the study of ancient magnetism. Everyday experience tells us that iron is magnetic; in fact, any metal containing even small amounts of iron ore is usually magnetized. However, when iron is heated to temperatures ~1000 K, it loses its magnetic properties as individual atoms jostle freely (which is why magnetic thermometers often fall off the side of a roaring wood stove). Hot basalt—the dark, dense stuff of volcanoes—impregnated with traces of iron and upwelling from cracks in the oceanic ridges, is thus not magnetic. As the basalt cools, magnetism sets in as each iron atom effectively responds to Earth’s magnetic field like a compass needle. When the basalt solidifies to form hard rock shortly thereafter, it fixes the orientation of the embedded iron, since the iron atoms align themselves with the orientation of Earth’s field at the time of cooling. Accordingly, the ocean-floor matter has preserved within it a history of Earth’s magnetism."

Rivkin · 13th February 2005, 05:28 PM

And it would not make a bit of difference to make swords from lodestones - they would lose their magnetization, just as any other piece of iron, during the heating process.

capt.smash · 13th February 2005, 05:56 PM

HI i might be out of my depth here but im sure i heard that if you take 2 pieces of metal and stroke them together in the same direction continualy for a long ..long time they eventualy become slightly magnetic[a labour intensive version of strokeing a piece of metal in 1 direction with a magnet ]..i have noticed this in old drillbits that develop magnetism from spinning continualy in 1 direction against metal.[i asume this is why they become magnetic]?
Perhaps smiths who use metal files could inadvertantly cause magnetism in blades from useing a file in this method, gradualy magnetiseing the file and then whatever blade he works on [this is relying on him haveing a fileing technique where he files only on 1 direction and lifting the file on the return stroke ]i see this fileing technique in woodwork but not sure about metalwork.
Also mabe this could be the case for a stone sharpeing/grinding wheel[if it had a slight metal content]?Also this might explain why some blades have diffrent strength magnetism on diffrent parts of the blade that required more fileing.
This may sound silly but i thaught id mention it

.

Jens Nordlunde · 13th February 2005, 06:25 PM

Rivkin, you explanation sounds most interesting, as well as you links, which I will read - and hope I will understand

.

I must say, that I am overwhelmed by the inputs and the quality of the inputs, thank you very much.

capt.smash, no you are not out of your depth, on the contrary. You are dead on mark. Yes the fils must be used only in one direction, or it wont work. All the litte pieces of iron would be all confused otherwise

. Thank you for answering.

Jens

Mare Rosu · 13th February 2005, 07:03 PM

JENS and all others good forum folks.
A most interesting thread indeed. I find little to fault with all the input but I have a question: How can one have two or more magnetic poles on the same blade? If you use a file, hammering or other means to magnetize a blade on purpose or otherwise, would you not have just one pole a North and a South pole on the blade. It is hard for me to figure out a process that would magnetize a blade with more than one North,& South pole without doing so on purpose by someone along the way. Leaving it in one place even for hundreds of years would still give you just a North and a South pole.
So my take is that a blade with more than one North and one South pole must have been done so on purpose.
Gene
Sorry

Fearn got it right this time.

Jens Nordlunde · 13th February 2005, 07:15 PM

Gene, you got it absolutely right - the way you describe it, is the way it must have been done - on purpose

.
Now the big question is why, and I doubt veru much that anyone can answer this question, unless we find some hints in old books. Should I find them, be sure that I will let you know.

Jens

13th February 2005, 05:56 PM	#4
capt.smash Member Join Date: Jan 2005 Location: Devon ,England Posts: 80	HI i might be out of my depth here but im sure i heard that if you take 2 pieces of metal and stroke them together in the same direction continualy for a long ..long time they eventualy become slightly magnetic[a labour intensive version of strokeing a piece of metal in 1 direction with a magnet ]..i have noticed this in old drillbits that develop magnetism from spinning continualy in 1 direction against metal.[i asume this is why they become magnetic]? Perhaps smiths who use metal files could inadvertantly cause magnetism in blades from useing a file in this method, gradualy magnetiseing the file and then whatever blade he works on [this is relying on him haveing a fileing technique where he files only on 1 direction and lifting the file on the return stroke ]i see this fileing technique in woodwork but not sure about metalwork. Also mabe this could be the case for a stone sharpeing/grinding wheel[if it had a slight metal content]?Also this might explain why some blades have diffrent strength magnetism on diffrent parts of the blade that required more fileing. This may sound silly but i thaught id mention it . Last edited by capt.smash; 13th February 2005 at 06:57 PM.

13th February 2005, 07:03 PM	#6
Mare Rosu Deceased Join Date: Dec 2004 Location: USA, DEEP SOUTH, GEORGIA, Y'all hear? Posts: 121	Question? JENS and all others good forum folks. A most interesting thread indeed. I find little to fault with all the input but I have a question: How can one have two or more magnetic poles on the same blade? If you use a file, hammering or other means to magnetize a blade on purpose or otherwise, would you not have just one pole a North and a South pole on the blade. It is hard for me to figure out a process that would magnetize a blade with more than one North,& South pole without doing so on purpose by someone along the way. Leaving it in one place even for hundreds of years would still give you just a North and a South pole. So my take is that a blade with more than one North and one South pole must have been done so on purpose. Gene Sorry Fearn got it right this time.

13th February 2005, 10:47 AM	#1
Jens Nordlunde Member Join Date: Dec 2004 Location: Europe Posts: 2,718	Hi all, Not all magnetite can become lodestone, it takes a special crystal structure, see what Dr. Peter Wasilewski, of NASA's Goddard Space Flight Centre, writes here http://www.phy6.org/earthmag/lodeston.htm this will answer some of the questions asked. Fearn, I am nor a specialist on this, but I would think, that if you fold a blade many times, it will loose magnetism. I agree with you, I also think the magnetism on blades was made later – but why? If we believe in what Dr. Peter Wasilewski writes, the lightening together with a good portion of superstition would lead them to believe that the Gods had made this metal. I don’t know if lodestone was ever used for weapons, maybe it was too difficult to get the iron out of the stone, or maybe the percentage of iron was too small, I don’t know – but one thing it could do, and that was making other iron weapons magnetic. If they believed that the Gods gave them this stone, they would also believe in, that using this stone to magnetize a blade would give the user more power. Nechesh, I know you did not advocating for magnetizing blades. I clean my blade and etch them, but I don’t magnetise them. The reason for this is that I don’t know if the blade was magnetised from the start, that is why I leave it be. Rivkin, it seems as if Dr. Peter Wasilewski does not agree with you about the magnetic felt of the earth when it comes to lodestone, maybe the magnetic felt could influence ancient pottery, I don’t know, and I don’t know the reason for this. I think you are right, that if any magnetism would be recovered in a blade after heating, it must cooled very slowly – just like the Indians did with wootz. The defects in crystalline structures, what other metal the iron was mixed with, even in very small doses must have been a problem for the smiths, as this would have affected the way the iron should be treated. It seems to me, that wootz from one ore might have needed a slightly different treatment than wootz from another ore, according to how the iron was mixed. But I never saw anywhere that the wootz ores were magnetic, only the lodestone. Robert, on the first link I gave, it somewhere say, that if you take a big nail which is not magnetised and hammer on one end for 50 times, the nail is magnetic – if you turn the nail and do the same on the other en of the nail, you will change the poles. Jim, I think a crude compass was made much earlier than about 11th century AD, try to read this: For many years magnetism was just a curious natural phenomenon and its only use was in navigation as what we now refer to as the mariner's compass and which was probably first developed by the Chinese some 4500 years ago. The earliest mariner's compass comprised a splinter of loadstone carefully floated on the surface tension of water. You can find the whole text here http://www.newi.ac.uk/BUCKLEYC/magnet.htm if you are surprised when reading this, I understand you – I was surprised too. Does anyone know if lodestone alone, or in combination with iron/wootz was used for making weapon? Interesting questions you ask – but you must remember that I am not an expert – I try to learn as fast as you ask the questions. yannis, interesting what you write to Jim, try to have a look on the link I gave him. Yes, filing on a blade can make it magnetic, but you would have to file in the same direction the whole time - not back and forth, and I think it would be an advantage if the file was magnetic. I doubt however if it would make a kard blade as magnetic as the one you have, but I don't know it. Jens

13th February 2005, 05:26 PM	#2
Rivkin Member Join Date: Dec 2004 Posts: 655	I believe that the case with Wasilevski is that his message have been probably perverted by "popular" explanation - probably what he meant is that extremely well magnetized samples have origins different from just being cooled in Earth magnetic field. Concerning the knowledge that ancient iron (whether in pottery, iron deposits or special spherical boxes lying on the ocean's floor) is magnetized alongside the Earth magnetic field at the time of the iron sample's cooling period is a well known fact, avoiding "real" papers I would bring your attention to: http://www.sciencetech.technomuses.c...fo_Magnets.cfm "Magnetite is magnetic because its molecular structure has allowed it to retain the alignment of particles caused by the Earth's magnetic field during its formation millions of years ago. When heated to high temperatures magnetite loses its natural magnetism. " http://www.tufts.edu/as/wright_cente...xt_plan_5.html "Finally, a fourth bit of evidence also favors the idea of plate tectonics, although here the data aren’t as robust, their implications not as clear. This evidence is supplied by paleomagnetism—the study of ancient magnetism. Everyday experience tells us that iron is magnetic; in fact, any metal containing even small amounts of iron ore is usually magnetized. However, when iron is heated to temperatures ~1000 K, it loses its magnetic properties as individual atoms jostle freely (which is why magnetic thermometers often fall off the side of a roaring wood stove). Hot basalt—the dark, dense stuff of volcanoes—impregnated with traces of iron and upwelling from cracks in the oceanic ridges, is thus not magnetic. As the basalt cools, magnetism sets in as each iron atom effectively responds to Earth’s magnetic field like a compass needle. When the basalt solidifies to form hard rock shortly thereafter, it fixes the orientation of the embedded iron, since the iron atoms align themselves with the orientation of Earth’s field at the time of cooling. Accordingly, the ocean-floor matter has preserved within it a history of Earth’s magnetism."

13th February 2005, 05:28 PM	#3
Rivkin Member Join Date: Dec 2004 Posts: 655	And it would not make a bit of difference to make swords from lodestones - they would lose their magnetization, just as any other piece of iron, during the heating process.

13th February 2005, 06:25 PM	#5
Jens Nordlunde Member Join Date: Dec 2004 Location: Europe Posts: 2,718	Rivkin, you explanation sounds most interesting, as well as you links, which I will read - and hope I will understand . I must say, that I am overwhelmed by the inputs and the quality of the inputs, thank you very much. capt.smash, no you are not out of your depth, on the contrary. You are dead on mark. Yes the fils must be used only in one direction, or it wont work. All the litte pieces of iron would be all confused otherwise . Thank you for answering. Jens

13th February 2005, 07:15 PM	#7
Jens Nordlunde Member Join Date: Dec 2004 Location: Europe Posts: 2,718	Gene, you got it absolutely right - the way you describe it, is the way it must have been done - on purpose . Now the big question is why, and I doubt veru much that anyone can answer this question, unless we find some hints in old books. Should I find them, be sure that I will let you know. Jens