A European four-in-one
(waist length shirt with sleeves) constructed from sufficiently small steel ring
s can weigh upwards of 40 to 50 pounds. This is in addition to any other mail armor (coif
s), plate armor (helm
shield, etc), clothing and weapons one might use in combat. Consider also that most medieval
chainmail pieces were made from iron
or mild steel
which is now very common), which tarnished and rusted, causing them to grow weaker and eventually break.
Consider now making a Tolkien-esque hauberk by using an aluminum alloy instead of steel. How much closer to mithril can one get? Aluminum does not rust or degrade; instead it oxidizes, protecting it from the elements. It is very strong. Most importantly, however, it weighs a third of what steel does. Suddenly that 40 pound shirt is a "magical" 12 pounds.
Considering that aluminum is a very "recent" metal in terms of the industrial age, there was nothing like it in medieval times. There is no telling how people in the 15th century would react to seeing a suit of aluminum armor ...
One might also use a titanium alloy .. with its very light weight and extremely high tensile strength. You could survive melee and then take a tank round!
I made a section of European six-in-one mail out of aluminum rings. This weave was considerably dense; a regular screwdriver would not penetrate or damage it. Repeated violent bashings of the small piece with a large shop screwdriver resulted in no damage. Such mail would probably be more than sufficient to stop arrows (and possibly crossbow bolts).
I've made several pieces of aluminum mail and they are awesome .. lightweight and extremely strong. You can wear it for hours without getting tired. Truly "magical" ..