[Gandalf_The_Gray]

the protective film was formed catalytically by the presence of high amounts of phosphorous in the iron—as much as one per cent against less than 0.05 per cent in today's iron.

Before everyone goes all ga-ga over the skill of the ancients, consider this. The reason that phosphorous is eliminated by modern metallurgical process is that it causes the iron to be exceedingly brittle, thus rendering it unsuitable for use as a structural material or say a cannon barrel. Perfectly acceptable for a decorative column or ballast weight however.

Regards,
GtG

[SampleMan]

Again, too many details! I have but one question. Can it be put to use as lawn furniture!?!? ;)

[Gorzaloon]

Before everyone goes all ga-ga over the skill of the ancients, consider this. The reason that phosphorous is eliminated by modern metallurgical process is that it causes the iron to be exceedingly brittle, thus rendering it unsuitable for use as a structural material or say a cannon barrel. Perfectly acceptable for a decorative column or ballast weight however.

And Parkerizing is the formation of basic iron phosphate on a surface to protect it from rusting. Not very "New", but loading the iron with phosphorous and leaving it in the rain is a tedious way to do it. Plus, as you say, the physical properties of the iron would be horrible.

[r9etb]

reason that phosphorous is eliminated by modern metallurgical process is that it causes the iron to be exceedingly brittle, thus rendering it unsuitable for use as a structural material or say a cannon barrel.

And that, sir, is why you're such a fine wizard.

Of course, had our ancient Indian metalmen been more patient, and added the charcoal somewhat later in the process, they'd have gotten steel....