Equestrian Geological and Gemological Society

The Equestrian Geological and Gemological Society ("E.G.G.S.") is an organization based in Equestria dedicated to various geology-based subjects. Their ranks include professors, students, and enthusiasts of rocks and gemstones of all kinds. At their annual conventions, members come to learn news about, admire, or peddle all things geology.

The society helped Maud Pie achieve her first major academic breakthrough as she and Rarity explored the Crystal Mountain Range as per the advice of Professor Strata.

Behind the scenes
Aside from Rarity, Maud Pie and Lyra, all identified members are comic originals. Buried Treasure, her two goons and Strata were created for the story, but the rest debuted in older comics. This is a trend in some of the more esoteric bits of lore in the comics, where they tend to reference their own continuity rather then rely on the show.