Down Cthulhu, The Occult Wars
Tom Spalding, when asked about Lord Percy and Rick Rathbone by Thomas Wilberforce:
“I knew you would ask about those 2 fellows. Let me tell you something: When one of those 2 are at a function for the Adventurer’s Club, each person there knows a larger sense of grandeur than they is present. When they are both in attendance, it is something different altogether. It is as Titans amongst giants. When they shake hands, an almost tangible reverberation pulses through the room (I experienced this myself first hand) and everyone instictively knows that something epic just occured.”
It is a bio-engineered wood infused with an organic-metal, previously unknown type of iron. It is hyper-sensitive to planetary magnetism so that one can build a ship out of the wood and fly on the electromagnetism. It degrades like metals, especially in moist environments. So, while it lasts 10 or so years on Mars after being cut down, it lasts about half that on earth. On Venus, it degrades even faster than calculations show for an unknown reason.
The alignment of the hull sections on the ship work with the magnetic field to easily supply more or less lift as you change the alignment of manipulating planks.