Friday, October 30, 2009

Iron Working

There is more iron in the world than every other kind of metal put together, by almost a factor of ten. Iron ore is wildly common, so common that whole landscapes are red with it. Powdered iron makes beaches and taints deserts, forms wide visible layers in bare rock and collects in layers at the bottom of ponds and lakes. It is a heavy, hard stone, twice as heavy as most gems – polished, it makes fine jewelry, and existed as jewelry thousands of years before it was founded as metal.

Iron is not as easily founded as copper – iron melts at a temperature 900 degrees hotter than copper. I quote from Daniel R. Headrick, Technology, A World History:

“The simple furnaces used at the time – pits dug in a hillside and lined with stones or clay – could not get hot enough to melt iron. What came out was a spongy mixture of iron and slag (or dirt) known as a bloom. To drive out the slag, blacksmiths had to heat and hammer the bloom repeatedly, a tedious process that required a great deal of time and charcoal. The result – wrought iron – was softer than bronze, cracked easily, did not hold an edge as well, and rusted rapidly. Yet iron had one tremendous advantage: its ores are found in large quantities in almost every country, often close to the surface, where they are easy to dig up.

“Gradually, by trial and error, blacksmiths improved their product. To prevent cracking, they learned to cool hot iron by dipping it in cold water. To make it less brittle, they tempered it by reheating the quenched iron several times. By repeatedly placing an iron object in direct contact with burning charcoal, they turned its surface into steel. By the fourth century BCE, blacksmiths were making iron swords with a steel cutting edge that was hard enough to cut through bronze.”

Note that we can posit from the above that although iron was being used extensively at the beginning of the classical age, bronze had not gone out of fashion in the seventh and sixth centuries BCE. The fifth century Spartan hoplites were still using bronze weapons and shields, as were the Romans and Etruscans during the period of the Roman kings (prior to 509 BCE).

But cheaper, quality iron would eventually replace bronze weapons. Virtually all the weapons in Alexander the Great’s army would be iron, as would the weapons of India when the two armies met in the Battle of Hydaspes in 326 BCE. Iron had been introduced in India about 1000 BCE; long prior to that, and prior to its discovery by the Hittites, iron had been used by the Chinese. Thus, by the end of the Classical world and the rise of Rome, it was an iron world.

For those DMs out there who are working on Mesopotamian or even Assyrian campaigns, iron should exist either as a cheap alternative to bronze, both inexpensive and inferior. On the other hand, a specific race that has properly learned to forge iron as it was forged in the fourth century might have a decided advantage over others.

Apart from things I talked about yesterday, hard iron weapons might effectively destroy weapons as they strike. The same might be said for mithril vs. iron swords, or even magical weapons against non-magical. Where is the table that demands a saving throw to be made by inferior grade metals against superior alternatives? Shouldn’t there be a chance that my iron sword will split my opponent’s wooden spear?

I’ve never come up with a simple, workable arrangement that allows this ... but it seems like something that should happen – not just once in a blue moon, but with frightening regularity. Suppose that with every to hit roll that results in a ‘19’ (as opposed to a natural 20), the opponent’s weapon must make save. Would it be worth it?

I think it would have to be judged in terms of comparative materials. A quarterstaff against a quarterstaff would not incur a saving throw ... nor would the quarterstaff cause the magic weapon to have to save. This would be a one-way process – and so the saving throw would have to reflect the difference between the two weapons ... it couldn’t simply be a flat save vs. crushing blow.

If my combats weren’t already as complicated as they are, I might consider this. If I had someone who could keep track of these things, I would definitely be working on such a table. But I don’t think it very important just now. I leave it to you, gentle reader, to work on it as you will.


Zzarchov said...

I have rules that deal with this in Piecemeal, as I was running a meso-american game for some time, differences in material mattered quite a bit.

The gyst is that weapons have a certain amount of damage they can take, or deal on a damage die + strength bonus.

When hardness ratings (not scientific currently though Im working on it) are taken into play it makes it even more noticeable.

Beyond this damage limit and they start taking considerable risks of being broken (cumulative difference between numbers on a d20, so if you exceed bronzes damage rating by 2, a 3 in 20 change, by 3 points and its 6 in 20)

A purely wooden shield would easily be smashed by an Iron battleaxe.

Key to this working is the defense system where you roll to parry or shield block. Thus if you block a powerful attack, it may smash your weapon in two.

This also means some materials are unsuitable to make some weapons, you can make a bone knife..but barring magic a bone longsword is out of the question, as it will easily shatter. Likewise a copper greatsword would be utterly useless beyond the first swing.

Narmer said...

I've been enjoying your metallurgical posts and you civ posts in general. Thanks.