No one knows for sure where and when mail was invented. The first mail was rings of wire riveted together, with 4 rings passing through a fifth. There have been all sizes of rings and wire, some so fine that the mail was like liquid steel, and others very large, thick and quite heavy, as is our version that we are offering. The wire has been flattened into washers to produce a much denser weave. It is very doubtful that a sword would be able to cut through this mail. It has also been dip galvanized so it will resist rust. 16 gauge steel.