Voidstone

Voidstone was a solid substance that originated on the Negative Energy Plane and destroyed anything it touched.

Properties
Completely black and featureless, voidstone was nearly unmeasurable by any known means. Rough estimates of size could be made by the black hole it formed in any region of illumination. Size could range from a few inches/centimeters to dozens of feet/many meters in any dimension. Any material touching it, other than another voidstone, was quickly destroyed in a matter of seconds&mdash;a being with great fortitude might have lasted a little longer. Telekenesis or other forms of mental control did not work on voidstones, but perhaps divine or other magical powers could be used to manipulate them. Some voidstones were attracted to life; the medium-sized chunks would move in the direction of the nearest living creature while the very small and very large pieces remained motionless. Voidstones showed no reaction to undead.

Fabrication
No means of creating voidstone were known. It formed naturally on the Negative Energy Plane in major negative-dominant areas when the ebb and flow of the energy tides caused an intense concentration of negative energy, creating seemingly stable chunks of voidstone.

Application
There is speculation that voidstone was the basis for the creation of sphere's of annihilation because of the similar destructive nature and utterly black appearance, but proof of an actual connection remains elusive. Needless to say, a piece of uncontrolled voidstone on a plane with gravity and an atmosphere would be extremely dangerous, possibly apocalyptic.

Appearances
Voidstone is seen in Lisa Smedman’s second part of the Lady Penitent trilogy, Storm of the Dead. It is mentioned by Q'arlynd Melarn that voidstone is a solidified piece of the Negative Material Plane.