From PathfinderWiki

The Gembasket spans an area in the Barrier Wall mountains approximately a mile in diameter, across razored peaks, unexpected drops, rocky ground, and impassable rises. Natural resources are abundant within the Gembasket, including nodes of gemstones, precious metals, and veins of minerals that run its rocky walls. A narrow and dangerous path navigable only by experienced travelers winds up through the mountains to the Gembasket.1