Sub-Roman Britain (Cavalry etc)

[Alanus]

The Norsemen peat bog process of smelting added silica into the mix when forging. This would add some form of rust resistance at least until about the third forging. Thus the blade being cast back into the lake according to Arthurian legend.
Let's not forget the magical Excalibur. :lol:

Well, the sword subject is a sore one, depending if you are a Celticist using corrupted medieval ms to post your case, or whether you are someone looking for an introduced source. One thing is historically clear, Celtic swordmaking was centered east of the Jura, not in Britain. The only documented Excalibur-type sword belonged to Morgan (grandson of Theodoric/Tewdrig), a Black Sea styled sword worth 70 cows, valued today as $46,000.

My guess is that both swords-- the Lady of the Lake's Excalibur, and the Sword in the Stone-- may have been a singular sword with duel functions. The etymological viability of Caliburnus is no truer than "Exchalybur," the last easy enough to denote "from chalybis" (read as "superior steel") or "from the Chalybes." In view of the well-recorded ritual sword Tyrfing, the mythical sword Excalibur could be grounded in fact. And the cultural connection swings to the Alans, Taifali, and Tyrfingi Goths, all of whom are prime candidates for late Roman cavalrymen in Britain.