Abyssal bloodiron is the end result of the remnants of uncountably many spent magics and gallons upon gallons of blood or ichor that in places have soaked into the substance of the Abyss over thousands of years. Found in thin striations all across the Abyss rather than veins, this metal is common amongst the tanar'ri, the chief constituent of demonic weapons in the Blood War and elsewhere. The eldritch energies that run through it are fragile until forged, and the metal must be treated carefully or else revert to naught but blood-soaked iron. When properly handled, though — cold-forged over an extended period of days upon days before a single hammer strikes it — the energies take firm root, completing the transformative process and allowing it to be worked into weaponry. Once processed, Abyssal bloodiron looks like normal iron or steel on the surface, but any honed edge appears blood-red, a deeper color indicating a finer blade.
When used in a weapon, Abyssal bloodiron, despite the name, counts as silver with regard to DR, and provides a +4 enhancement bonus to confirmation rolls for critical hits. Weapons made of Abyssal bloodiron are 3x normal price and must be masterwork. It is otherwise equivalent to steel.
- Planar Handbook, pg.69