Bastion and Beyond
Soarwood is a psionically resonant wood that is necessary to construct airships. It is 1/10th the weight of regular wood but just as durable, and is able to resist the powers of the air elementals bound in airships.
Rhyndalwyn grew soarwood in the Soarwood Mines, where it grew from the ceiling downwards, seeking the powerful psionic mind of an Aboleth of the Underdark. These mines have been destroyed, and the aboleth has dissapeared.
Also known to grow deep in Thelanis and in the Astral Plane.