Various black metal artifacts reputably from the ancient Tsuankhotal Empire supposedly dot the forests and jungles of Vheld. Legend has it that these mysterious black metal objects (MBMO) are indestructible and possess arcane powers. These MBMOs range from bits of ancient machinery to more practical objects like ceremonial axes and weapons with "arcane" powers. Unfortunately, no one really knows how the early Tsuankhotal Empire made the black metal. The technique has long since been lost.
So far, there has been no unequivocal evidence for this artifacts. The axe described in 0047: Gareth's Tale pt. 2 and the gizmo that Gareth Tyran unearthed in the ruins of Melas in 0048: Gareth's Tale pt. 3 appear to be these sorts of artifacts. Toby Chapman researching in the Alistaire Menterosa Memorial Library, he found information about a strange black metal object that Arthur Wellington find as seen in 0059: Artifact
However, until such items have been presented to recognized authorities for inspection, MBMOs are nothing more than fanciful legends and fodder for dreadfuls.
Conspiracy theorists speculate that a few researchers who have obtained a sample to try and study it have been slowed by the fact you cannot remove a sample of the indestructible metal. Add to this the fact that any research is probably top secret, and it means that chances are no one living today knows how the Hell the metal was ever made.