Interesting thought...
The
Shadow World Players Handbook has this to say on the subject:
Xenium—Blue-silver in hue, Xenium is the only alloy listed here and deserves mention for its famous use, which is on the underside of skyships. The alloy somehow nullifies the force of gravity but the exact manner in which this is accomplished encompasses many factors and are extremely difficult to calculate, or understand.
This
perhaps implies that it’s not currently in production as it’s
extremely difficult to calculate, or understand...but the
Master Atlas paints a more definitive answer:
Xenium (1000 sp): Blue-silver in hue, this alloy is created from titanium, arinyark and other—more dangerous—materials, which together nullify the force of gravity. It is used primarily on the undersides of skyships. The exact manner in which this is accomplished, and how Xenium is successfully employed to balance a ship’s mass against gravity, are factors which are extremely difficult to calculate. The price given is the ‘street’ value; obviously the alchemists who created Eidolon and who make the skyships were able to make such vast quantities that the relative cost was considerably less.
The key point is that it refers to the alchemists who
make the skyships - present tense
But you can make the Shadow World your own and say whatever you wanted - but cannon says that it’s still being created but the calculations needed are very complex and the alchemists won’t share those formulas. Specialist tools are also required in its creation (mentioned elsewhere in the
Master Atlas) which you’d need along with the formulas if any player wanted to make their own antigravity vehicle for themselves.