Sourcenatural - Hells, very rare - Felbarum

Arjale is a metal that is jet black, light in weight, easily worked to a smooth surface, and can be brought to razor sharpness. If alloyed with iron, it becomes light green-grey in color, and quite pliable; sometimes called "dajavva".

Edged weapons made of this material score and additional +1 damage. Arjale is impervious to acid. Arjale is found naturally only on worlds of Hells system. On Bal-Kriav, the wasteland Felbarum has some of this metal buried around and stuck in the petrified neck and head of the dead primordial Bryakus.