Imagine being a scientist, and being told that your mere presence in a facility would alter the crystals being grown, that no joke you cannot step foot inside: Scientists who had been exposed to Form II in the past seemingly contaminated entire manufacturing plants by their presence, probably because they carried over microscopic seed crystals of the new polymorph Fact, not fiction! In materials science, a disappearing polymorph is a form of a crystal structure (a morph) that is suddenly unable to be produced, instead transforming into a different crystal structure with the same chemical composition (a polymorph) during nucleation and points for being airborne! In a few cases, such as progesterone and paroxetine hydrochloride, the disappearance gradually spread across the world, and it is suspected that it is because Earth's atmosphere has over time become permeated with tiny seed crystals https://en.wikipedia.org/wiki/Disappearing_polymorph #science #TIL #crystals