jarnbyrþ (OSw) járnburðr (ON) noun

The bearing of a hot iron, a trial by iron, an ordeal. A trial of hot iron was prescribed for men in certain situations which called for an ordeal (skírsl, see skærsl). Ordeals for women usually involved boiling water (ketiltak), but in SkL a woman could be forced to undergo an ordeal by hot iron in cases of suspected adultery. The trial of hot iron may have been imported to Danish-ruled Estonia for a time during the thirteenth century (cf. Vogt 2013, 240–41).

iron-bearing ONorw EidsL 45.3
ONorw FrL ArbA 16
ordeal ONorw FrL KrbA 45 Mhb 5, 23
ONorw GuL Krb, Mhb, Leb
ordeal of hot iron OSw ÖgL Eb
test of the red iron OSw HL Äb
trial by iron ONorw EidsL 3.3 Refs:

KLNM s.v. gudsdom; LexMA s.v. Ehebruch; NGL V s.v. járnburðr; Nilsson 2001