Apergium

Nature: Magical alloy
Forging Recipe: The Riders of Pegasus, Volume III
Info: The following is from Skadi's translation of the Book, pages 148 & 151:

APERGIUM: Requires both mastery of matter and adept competence with forces. While the Mysterium could easily reproduce the Cavorite with the rotes and materials they found at the crash site outside Cape Town, the writings about an even more potent alloy were too incomplete to provide any means of easily replicating said metal. It took research mages nearly 20 years to rediscover it, mostly because the ^m_in^a_g^t_r^e_e^r_dⁱ_i^a_e^l_n^s_ts are so unusual. In addition to the Khronicum and aluminium required for Cavorite, apergium (as it was called) also contained brass and quartz crystals. It is believed that this was indeed the metal used to propel the Owsley-Palmer expeditions in the early twentieth century, though recent advances in sleeper interplanetary surveillance systems has made copying said excursions unfeasible (prob infeasible). To most.
tab The metal itself resembles cavorite, but glows much more _i^b_n^r_tⁱ_e^g_n^h_s^t_e^l_l^y_y, and is notably colder than the environment. The most powerful aspect of it is that it has negative gravity (called apergy), instead of being attracted to large bodies of matter it is repulsed by them. Between small amounts of matter, like humans, this repulsive force is negligible, yet in relation to Earth it is formidable, just like with mundane gravity. Apergium has approximately the same density and weight as lead, though the direction of the weight is opwards (prob. upwards) of course away from the gravitational field of Earth. Each point of potency generates about one pound, or anti-pound, of alloy, bot (prob. but) it retains its frael (prob. frail) nature no matter what.
tab Ironically, to use apergium effectively requires cavorite, which explains the presence of both metals at the site. Since cavorite shields against all gravity-effects, it is the only way to "turn off" the anti-gravity the apergium produces. By containing it within cavorite shields and sluices, the gravitational lift can be turned on and off at will. the onlv (prob. only) other way to keep it from shootinng (prob. shooting) off into space is to weigh it down with other substances, and so is (prob. it) is among the very rarest of magical alloys to be found in ruins, since most of it has a tendency to disappear into the blue long before any explorers can find it.

Note: Primarily Infernal writing, with the underlined words written in Norse runes
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