![]() |
|
![]() |
#1 |
Member
Join Date: Dec 2004
Location: Europe
Posts: 2,718
|
![]()
Lodestone, or magnetic stone with iron, have been known to exist in India for several thousand years, and was very early used for the first compasses, as it, when put on water will turn so it points north south.
Does anyone know if it was used for weapons? Maybe the content of iron was too little, or maybe it was too soft. What is the reason that we hear so much about wootz and so little about the magnetic lodestone? When you forge you will need heat and a hammer, and when you cast you will need heat – both heat and hammering kills magnetism. So whatever magnetism a dagger or a sword have, it must have been made after the weapon was finished. I have a tulwar where the blade is magnetic on the middle but fades out, it can pull the needle from N to ESE or about 130 degrees, but the hilt can pull the needle all the way around It is known that cast iron is easier to magnetize than forged iron, due to the rough structure of the iron, but it is also known, that cast iron looses the magnetism easier than forged iron. The finer the structure is the harder it is to magnetise the blade, but the longer it will stay magnetised. I don’t know how long time it would take, for a wootz blade to loose its magnetism, or for a cast item for that matter, but if a blade has been magnetised from the start, and it is, maybe two hundred years old, there is reason to believe that some of the magnetism has been lost – but how much? Why make a blade magnetic, and a magnetic hilt is an even bigger puzzle. The only answer I can come up with at the moment is, that only few knew how to magnetise, and that a magnetised blade was magical. But is that the right answer? Does anyone know the answer, and those of you who have magnetic blades, are this blade of high or of average quality? On this page you can read about magnetism, it is rather interesting. http://www.newi.ac.uk/BUCKLEYC/magnet.htm And on this one too. http://my.execpc.com/~rhoadley/magindex.htm Please take a number and queue up before answering ![]() Jens |
![]() |
![]() |
![]() |
#2 |
Deceased
Join Date: Dec 2004
Location: USA, DEEP SOUTH, GEORGIA, Y'all hear?
Posts: 121
|
![]()
JENS
"Please take a number and queue up before answering" You pose a very interesting question on blade magnetism. I have for the last week or so been testing my wootz daggers for magnetic fields. One I call the Mysore dagger has some very unusual properties (at least to me that is ) starting at he hilt end of the blade a compass will change direction four times! with the needle pointing N then S then N and then S again at the tip of the 12" blade. I have no idea as to how this magnetic properties were "added" to the blade or for what reason if in fact it was done knowingly at all. I have two Wootz ingots that are original ( not forged into a blade ) that show no such magnetic properties, which would lead one to believe that the magnetic properties were "added" after the blade was completed. I am in the process of working up a visual display of the magnetic fields on this dagger and will post pictures when and if it works out. Again you pose a very interesting subject/question, you do have a tendency to ask hard questions. ![]() Gene |
![]() |
![]() |
![]() |
#3 |
Member
Join Date: Dec 2004
Location: Europe
Posts: 2,718
|
![]()
Thank you Gene. Your dagger sounds to be rather unusual, and very interesting
![]() When I wrote the thread I must have been somewhat unconcentratet, as I forgot to give a link to the lodestone, here it is - sorry. http://www.phy6.org/earthmag/lodeston.htm Jens |
![]() |
![]() |
![]() |
#4 |
Member
Join Date: Dec 2004
Posts: 1,247
|
![]()
Hi Mare Rosu,
Can you make up a story about the magnetized knife lying on top of a horseshoe magnet or two at some point (the legs of the horseshoe perpendicular to the blade). That would give the magnetic pattern you describe. I suppose the other way you could magnetize a blade is to put it inside a big coil for a while with the power on. I think the problem there would be keeping the blade from acting like the center of a solenoid and getting shot out, possibly at high speed.... ![]() Neat stuff. My question is, why would anyone want to do it, unless it's the usual "sword mysticism" kicking in? |
![]() |
![]() |
![]() |
#5 |
Member
Join Date: Dec 2004
Location: Cincinnati, OH
Posts: 940
|
![]()
Jens, you may find the very first thread i posted of this forum of interest:
http://www.vikingsword.com/ubb/Forum1/HTML/001099.html I have been very interested in this subject for some time. For me, the answer to why magnetize a blade is indeed "sword mysticism" kicking in. The first thing i do when i receive a new keris is to check it for magnetic polarity. Most often it is farly weak or dead, but i have received a few blades with a very strong polarity. But even if the polarity is gone i create it. It is a VERY simple process. I have a very powerful magnet that i place the tip of the keris on, and after reciting a few highly secret magickal incantations ![]() ![]() ![]() ![]() |
![]() |
![]() |
![]() |
#6 |
Member
Join Date: Dec 2004
Posts: 655
|
![]()
I'm sorry if my idea will be completely stupid, but I don't find it to be a proof of "magnetization on purpose".
Very small pieces of pure iron (and most steels) are magnetic (ferromagnetic) due to their nature. It looses it's magnetic properties when heated, but regains them when cooled - to what extent depends on the way the cooling is performed. If it's rapid the magnetization after the cooling will probably be small, If it's gradual the sample will fully regain the full magnetization (ordering), which will mostly depend on sample's shape and chemical composition. Now if the piece is not a microscopic one, then the magnetization is due to the fact that when the large piece is cooled it has to be under the influence of magnetic fields (magnetic field of the earth -this is actually how we know that it did decrease during the past 1000 years, anvil, hammers etc.). So if one has a sword that has nonuniform magnetization it can be that this sword for example was wielded from a few different pieces. It can be that the chemical composition varies from side to side (sulfa, chromium I think do kill magnetization quite easily). It can be that while cooled it was lying next to a huge magnetized hammer, so that the external field itself was extremely nonuniform. Again, the way cooling is performed is very important. Very rapid cooling usually prevents the formation of a magnetized state. So if the blade for example is differentially heat treated it is possible that it simply has different magnetic states present due to this fact. Such swords rather then becoming demagnetized with time would first actually become uniformly magnetized, and then would assume some magnetization due to the current earth's magnetic field (if it lies in the same place all the time), however it's even a big question if this _ever_ happens (it well may be that the current magnetized state is so efficient that it should take unphysically long time to change it using weak fields and temperatures). Sincerely yours, K.Rivkin |
![]() |
![]() |
![]() |
#7 |
Member
Join Date: Dec 2004
Posts: 655
|
![]()
And yes, placing a very powerful magnet (or taking it to a site of huge iron deposits) will "fix" the new magnetization even in a forged sword.
|
![]() |
![]() |
![]() |
#8 |
Member
Join Date: Dec 2004
Location: Europe
Posts: 2,718
|
![]()
Hi All,
I have not reread all the posts on this old thread, so I don’t know if it was here I mentioned that Jahangir ordered a dagger made of a meteoric stone, but I have found a picture of Jahangirs meteoric knife dated 1621 AD, it is in Freer Gallery of Art, Smithsonian Institution, Washington D.C., and it is showed on page 82 in Jewellery Studies, vol. 10, 2004. The article was written by Robert Elgood (pp 76-98) |
![]() |
![]() |
![]() |
|
|