Emerald Emergence
The Emergence is a supernatural phenomenon which accelerates the geological formation of emeralds in the Empire of Oz. For approximately three evenings each fortnight, a process which should take millions of years instead takes only hours. And nowhere in Oz is the process more visible than in the Rock Garden of the Emerald City, where the emergence is celebrated as sign of increased fertility in the land and in its people.
Manifestation
Once every 13 days, the forest moon of Yígkéké completes its circular orbit around volcanus infinitus. For the three nights when Yígkéké looms large in the western sky, between 242° and 298° in its orbit, the geological processes required for the formation of emeralds are magically accelerated.
Localization
The magic is limited to the subcontinent of Ostké. The phenomenon has been observed nowhere else in Eden.
Impact
Because of the localized effects of the Emergence, the mines and quarries of Ostké have been hotly contested since the dawn of the First Age. The magic only accelerates naturally occurring processes, after all, which means emeralds are still relatively hard to come by—and therefore still seen as a luxury outside of Oz.
The Emerald City was founded where it was not only because of its proximity to Lake Viridescent and the River Quad, but because of the so-called Rock Garden—a place where the effects of the Emergence are easily observed. This small boulder-strewn hill is lousy with beryllium, chromium, and vanadium and produces a sizable crop of gemstones every month. Sure, there are more to be found in the mines below the city, but if it hadn't been for the Rock Garden then the founders might never have known to mine here in the first place.
Finally, a word must be said about the prevalence of date nights in the Garden during the Emergence. Though many of today’s youth publicly claim that making out at the Rock Garden is “tacky,” given that it’s something their parents used to do—and their parents before them!—the evidence suggests the location is still as popular as it ever was. The clean-up after night 3 is, like, a whole thing.
Well I would not want to be part of that cleanup crew!
Neither would I. There's another profession article, if the right prompt comes up.