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. Within this area, natural resources lie thick and abundant. Nodes of gemstones, precious metals, and veins of minerals run the rocky walls. A narrow and dangerous path winds up through the mountains to the Gembasket, and only experienced travelers can follow the path.1