After doing some fairly intense research on the matters of different types of materials suitable for edged weapons, I have concluded that much of what is written or thought about the various metals, is unquestionably bullshit.

For a considerable time, I was of the opinion that Stainless steel is unsuited to sword use, this opinion was based on fictions I had heard or read. For instance the idea that stainless cannot be "heat treated" is absolutely wrong. The truth is that only "some" alloys of stainless steel cannot be "heat treated". Other stainless alloys CAN be.

No one knows exactly when iron was first mixed with carbon to make steel, but the information we do have suggests that steel was made accidentally very early, say around 2000 bc. There are many types of carbon steel, some are suitable for swords, and some are not. Just because someone hands you a chunk of carbon steel, does not mean you can make a sword out of it. Some steels shatter at high heat if you hit it with a hammer.

From what I have found, "wrought iron" is actually a form of steel. Cast iron is NOT steel. Steel is made by combining iron and carbon. There are various methods of combining the carbon with the iron, some methods produce steel suitable for a sword, others do not. Some steels are not suitable for edged weapons because of other impurities such as sulfur or oxygen being mixed in with the iron during the process. Some steels were produced that only have a thin skin of actual steel forming over a core of iron. Some steels are too soft, some are too hard. The soft steels will bend, with little tendency to spring back, the hard steels break, without bending at all.

Until the 1800's steel was produced by trial and error, the processes were recipes handed down through (usually) religous ceremony that seemed to work much of the time. Some suggest that much of the success was due to the length of time it took to recite a specific prayer during a process. Of course the recipes were quite specific in the types of materials used.

In any case it seems clear that until scientific expertise was applied to the problem of producing steel, the steels in use as weapons were more likely to be grossly inferior than superior to modern steels. Stainless steels were developed about the same time that methods for producing carbon steels were generally accepted.

Stainless steel is merely iron mixed with Chromium rather than Carbon. There are alloys of stainless that add other elements as well, but it is the chrome that makes stainless. The first stainless steels were carbon steel mixed with chrome, but it was soon discovered that removing the carbon made a much higher grade of steel. The first commercial large scale stainless productions began in the early 1900's.

With that background, I begin with wood, bone and stone. It is fairly obvious that before metals were discovered, men relied on wood, bone and stone for weapon materials. Some woods can be honed to a fair edge, although it is much easier to use a stick to poke with than it is to cut with. Bones can usually be honed to a rather good edge, comparared to most woods, again, it is easier to make a point than an edge from a bone. Stones are difficult to fashion an edge from, except for the ones that naturally break into thin sheets with sharp edges. I'ts easy to imagine that it did not take very long to discover that composition weapons could be crafted that were superior to single materials, and more versatile in use. Generally taking a bone or stone edge or point and adding a wooden haft of some sort.

It was undoubtably copper that was first smelted and used for weapons. However it was adding Tin that made bronze, and the bronze age lasted for perhaps 2000 years, sharing about 1000 years with the new metal Iron. Because iron was smelted from wood burning it is certain also that sometimes under certain conditions some iron was actually steel of sorts, and was much superior to plain iron. As time went by, certain aspects of the process making iron from ore were recognized as the steps to making steel, though of course at that time no one actually understood why steel was better.

There are many many ways of making steel that are not any good for a sword. and only a few that produce a superior weapon. Then even if you start with good steel, it must be "heat treated" properly to make a superior sword. Heat treating is a process of heating and cooling a metal in various ways to make it harder, or softer. For steel, the process means heating to a specific temperature, cooling rapidly, then reheating to a lower temperature and then again cooling rapidly. Generally the target result of the heat treating process is to produce a piece of metal that is uniformly hard enough to take and hold an edge, springy enough to withstand flexing without breaking or bending, and tough enough to absorb impact without splitting, shearing or chipping.

If you make the steel hard enough to hold a fine edge, it becomes likely to shatter or chip upon impact, if you make it softer, thereby tougher, it is less spring, and less able to hold an edge. The point is that heat treatment can only make steel softer, or harder, period. Steel can be made too hard for a sword, likely to shatter, or too soft, likely to bend and not able to hold a fine edge. The target is somewhere in between, able to hold a reasonable edge and able to withstand impact without shattering.

There is NO magic involved with making steel, although through the ages there was quite a bit of mystery caused by ignorance. For instance there are still people who think that old folded steel blades from Japan are somehow endowed with a magical energy that makes them far superior to any steel made today. This is nonsense. Unfortunately the folding of steel layers does, in SOME cases make a superior edged weapon. There is no mystery here either, once we understand that the layers that were folded were of different steels!

If you take two steels, one high carbon, the other lower carbon and heat treat them both exactly the same, each will perform differently, one will be harder, the other will be softer. We know this from research into how steel is made and how they react to heat treating. If you now take those two pieces of steel, and start folding them together, over and over, you will end up with a single piece of steel with many layers of differing hardness. If you then make a sword from that steel, heat treating will insure that some layers are much harder, others are softer. Depending on how the layers were folded, and how many times they were folded, the layers could be extremely thin and if the sword fashioned so that those layers intersect the edge at a diagonal, then when the edge is honed, the softer layers will be ground deeper, leaving the harder edges sticking out like saw teeth. The first micro-serrations. Yes, these blades when properly made will outslice and dice any single steel blade it is put up against. These blades were often made with a differential tempering as well. This means that the heating cooling was done differently on the edge, making the edge harder, easier to keep sharp longer, and the back was softer, tougher, able to withstand impact. One other advantage of folding steels, is that by using thinner pieces of material, and folding them together, the blade was much more likely to be fully steel throughout, rather than a thin skin of steel encasing a core of iron.

The Japanese were not the only peoples who folded steel for weapons, however from my research it seems obvious they were folding it on purpose, knowing that the result would be a slicer. Other peoples seemed to be folding steels merely because they could only get a chunk of steel large enough to make a sword, by folding many smaller chunks together. These weapons were generally of poorer quality because invariably some of the steel was not good for swords, making stress cracks and breakage common, throughout the processes of making the sword, and during use.

What I find most interesting about the debate between stainless and carbon is the fact that a debate exists at all. Which metal is better suited to making a sword is best answered by discovering what uses the weapon is expected to task. If a sword is expected to nothing more than rest quietly in a display, then stainless is the obvious choice, very little care is required. If the sword is expected to reflect historical accuracy, then any period prior to the early 1900's would require a carbon steel blade. (or perhaps iron, to be really accurate) If the sword is expected to handle actual combat, (huh??), then I would prefer stainless, with a full tang hilt and riveted scale handles.

Stainless steel is manufactured to exhibit specific properties, and can be made so that it is NOT affected by temperature extremes normally found in the environment. For instance, in bitter cold, iron will shatter with impact, many carbon steels when heat treated will also shatter at low temps upon impact. If Carbon steel is subjected to temperatures approaching those found in any moderate campfire, whatever temper was given to the blade by the maker will be lost, so you better not go poking around in a fire with your carbon steel blade, you'll ruin it. Of course your carbon steel blade will rust also, especially that fine edge you may have spent hours getting razor sharp, merely by carrying the blade in a leather sheath on a moderately humid day, and your edge is a mess.

What many people dislike about cheap stainless swords is not in reality the fact they are stainless, but that they are cheap. Soft alloy, poor hilts etc. Stainless steel is generally more expensive than carbon steel, but the manufacturers of cheap swords know that the real expense is in machining and heat treating, not the raw steel itself. They use soft steel, and have no intention of heat treating it. Chop it up, grind it, weld on the tang, affix the hilts, and ship it, done. It looks like a sword, but it's not. Stainless steels that are hard enough to hold an edge are much more expensive to machine. The knife makers use stainless alloys that are harder than what is good for a sword, so their tools will work. Manufacturers of steel make stock that is big enough. I think the reason that we don't see many quality stainless blades is pure historical nostalgia. I have seen some very nice blades made from good stainless stock, that are totally useless because the manufacturer chose to make the piece "historically accurate", meaning the hilts will fall apart long before the blade fails, probably the first time it hits anything more substantial than a pillow.

In closing, the only discernible reason a person of reasonable intelligence would choose a carbon steel blade over a stainless steel blade is ignorance. I do understand that there are people who want a sword that appears to be from the 13th century, or whatever, but the fact is that swords from earlier than the 1800's were generally made of poor quality steel, (if not mere wrought iron), poorly made with weak hilts and likely to fail unless carefully left to rest up over the fireplace. If you really want a sturdy sword that will last and perform under extreme conditions and circumstances, you will agree that a Stainless steel blade, full tang with riveted scale handle is your obvious choice.