The Oglana Vault is one of the older buildings in the city of Oglana, constructed to contain the Ikaspi merfolk's precious supply of viridescenite.
On the outskirts of Oglana, a settlement of the Ikaspi merfolk off the coast of the Barren, there lies a small, closely-guarded series of viridescenite caverns known as the Viridian Hollows.