Work for us, and you'll be a minted man by winter.
Forged out of arcanium and emblazoned with a unique harmonic rune, the genuineness of a Mintmark can be easily verified with the pulse of a scanning chime. The harmonigram can be scripted to resonate with either sound or light. This can be done even from afar, allowing patrol skiffs to identify the credentials of ayrships by the resonance of their Mintplates. Individuals most often wear their marks around their necks, on a ring, on the buckles of their belts or hats, or the inside of a pocket watch. To prevent theft, a Mintmark may also feature a ferrotype image of the bearer, imprinted on a thin metal plate.
At first glance, a forgery may visually resemble the real thing, and those skilled in working with bifrostium harmonigrams might even mimic the resonant effect. However, even when these features are fooled, the artifice of the forgery can be revealed through the application of a corrosive litmus compound. Just one brush of diluted aqua domina would cause an ordinary metal to tarnish, whereas arcanium retains its lustrous sheen.
For Very Important Passengers Only
For most Gahlans life is a slow and grinding forced march northwards. To stand still is to eventually submit to the entropic pull of the abyss. Travel too far though, and all that awaits is the cataclysmic wall of the Kalyptian frontier. The trick then is to always stay in the good graces of the lords and governors that oversee citizenship on the spire-anchored cities found in the temperate skies of Panazur. Ever on the lookout for drifters, pariahs, and rogues, every sovereign maintains a complicated bureaucratic network of magistrates, ministers, and assessors that check the credentials of anyone deemed suspicious.
It can happen at the skydock, at the bank, at the flux station, the postal rookery, or even mid-flight. Wherever a Gahl goes, one can expect to encounter a checkpoint where identification will be needed. Paper documentation is easy to forge, and typically considered only fit for temporary purposes. Any given day might bring a cloudtide that covers an ayrland in mist, making paper a liability unless properly sealed against the elements. Metals like coins and medallions provide an additional level of security and durability, but even these can be fabricated by the savvier criminal elements, provided the hands are skilled.
For the highest levels of clearance, meteorite-derived metals like arcanium and stellarium boast unparalleled reliability, for one simple reason: Meteorite can only be worked in the sweltering volcanic bowels of an earthspire. And rarely is there a spire that is not securely under the control of a legitimate sovereign, or a well-established (and amply armed) trading company.