7
$\begingroup$

Let's say a 1600s civilization is around, making lots of iron objects: guns, swords, farm implements, etc. One day those people vanish.

What conditions would allow their iron implements to be usable, not merely recognizable, centuries later? (If it matters, say 200 to 600 years go by.)

$\endgroup$
  • $\begingroup$ Here's an interesting article I found about ancient iron implements. I can't quite tell why they were preserved so well, though: ancient-origins.net/news-history-archaeology/… $\endgroup$ – sumelic Mar 28 '16 at 8:16
  • 1
    $\begingroup$ Too lazy to write an answer, but think about a desert area with very little rainfall. $\endgroup$ – Xandar The Zenon Mar 28 '16 at 13:31
  • $\begingroup$ You store them in the Tower of London :-) $\endgroup$ – jamesqf Mar 28 '16 at 18:22
  • $\begingroup$ @jamesqf, storing them somewhere like that isn't actually a bad idea. $\endgroup$ – Joe Mar 28 '16 at 22:46
  • $\begingroup$ Also having them in a dry climate helps. There are a lot of iron artifacts hereabouts (intermountain US west) that would be fairly usable despite having been in the open for ~150 years. As for instance this rifle found recently: nationalparkstraveler.com/2015/07/… $\endgroup$ – jamesqf Mar 29 '16 at 18:56
8
$\begingroup$

Here are some of your options:

1- Boiled Water In Sealed Container

Boiling water removes the dissolved air in it and if you put an iron object in such water, it will not rust (6 grade experiment). But you will have to seal that boiled water container in order to protect it from dissolving air again (which would rust the iron).

2- Stainless Steel (Alloy)

This requires a carefully prepared alloy of Iron, Chromium, Nickel and Carbon. For best results, Molybdenum is also required, but since it is so rare, it be very hard for your people to have it and use it for preparing the perfect quality of the alloy.

3- Waxing

If you clean your iron objects and then carefully seal them with melted wax, they would remain rust-free. As sumelic mentioned in a comment, peat would work likewise. Wax would be a better choice than peat due to easy availability and it is much easier to remove too.

$\endgroup$
5
$\begingroup$

No oxygen and moisture. Actually not that hard. Something similar to cosmoline would form an effective barrier. Basically something thick and goopy which won't react (too much) with iron, and reacts the right way with oxygen. This simply means they'd care about the objects enough to pack them away properly. I'd also add, hardened cosmoline is a pain to remove.

I'm thinking tar might work, but can't really find any literature to it.

Sacrificial protection might be another option - zinc was smelted in the 6th century and available in pure form in the 9th century. If folk noticed that it kept stuff from being damaged in contact with the metal, and valued it enough to store their iron objects with a ton of zinc ingots in contact with them

$\endgroup$
  • $\begingroup$ It looks like peat might do it (it's also an excellent preservative for human bodies): books.google.com/… $\endgroup$ – sumelic Mar 28 '16 at 8:16
  • $\begingroup$ Peat has the risk of braking down the iron rapidly if any air gets in. $\endgroup$ – Bellerophon Mar 28 '16 at 17:28
3
$\begingroup$

High phosphorus content in the iron they were using. This is something that could happen accidentally as a quirk of the local iron ore or this people's way of smelting it. The result is that as the metal weathers, a protective coating develops.

Look up the "Iron pillar of Delhi" for further information. In modern times the same trick has been used deliberately to manufacture weathering steel which develops a thin patina of rust but which does not corrode further.

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.