I am wondering what our mail enthusiasts theorize about how maile and the source wire material was made before late medieval era. A couple of puzzles I don't have a firm opinion on;
1) Was the wire mostly formed by manual forging in anvil grooves, by sheering plate into strips and drawing, or completely random variations of both. (History of drawing equipment for iron alloy wires has been difficult for me to find before 15th century, but, that does prove it was not done.)
2) Were the raw materials used to make mail wire specific to one region of origin (statistically uncommon iron purity and phosphorus)? Or was the knowledge of how to make easily worked wire of chemical composition that we see in actual specimens (possibly from highly wrought iron worked in charcoal with a phosphorous adding material such as bones) something done over a wide range of Northern Europe?


I have been looking at the most detailed analysis of mail fragments I could find. I noticed that the few examined over a span of several centuries for chemical composition turned out to be uncommonly high purity iron (carbon less than 0.06%), with what would today be considered high phosphorus content (0.1 to 0.13%.) It could be a coincidence, but this is what higher quality "drawn iron wire" was at the beginning of modern industrial history before the chemistry and control of carbon were well understood. (Reference 1800's suspension bridge cables, harpsichord strings... today Rose type B piano wire is probably the only example..but is only available up to 0.8 mm diameter which is a little small for mail.) This composition also can be ductile with progressive hardening throughout cold work. If done just right, mail MIGHT have been fabricated with much less annealing steps than some discussing use of mild steel wire today seem to advocate.

1. It is fairly certain that the Romans practiced wire drawing.
There are at least two draw plates dating to the Roman period
Dimensional consistency of Roman mial links can only be explained by witre drawing
Alignment of slag inclusions are consistent with wire drawing.

2. Only high quality bloomery iron can be pulled through a draw plate. If the slag inclusions are too many or too large then the wire will constantly snap while being drawn. I don't think that the metallurgical properties of wire or mail can be used to tell where it was made since good quality iron would have been widely traded.

The addition of phosphorus decreases the ductility.
The quality is damaged. I think iron + phosphor was no good to be draw.
The Egyptians and Sumerians used the process to the jewelry.
The Romans certainly for the iron. and 'doubt if they used a machine to produce in large quantities. Personally I think possible, as building a machine for drawing is easy. The Romans built things much more complex.
Ciao
Maurizio :)