Sacred Instruments

 is a task in

Synopsis
A woman named Ista is trying to recreate the alchemical instruments by which the Battery dwarves first located the site upon which they erected their fortress. She has a prototype she wants tested - if someone will brave the wilds to do so. Ista is certain that her device works similarly to those used by the dwarves of Durgan's Battery to divine the location of valuable metals. She has asked me to test the device on the mountainside surrounding the Battery.

Walkthrough

 * To start the quest, talk to Ista on the docks near the Temple of Ondra in Stalwart Village. After a brief discussion, she'll hand you the Ore-Locating Device and will send you on your way.
 * Standing near certain locations around the exterior of Durgan's Battery will change the direction that the device points towards, ultimately directing you towards the cavern to the west.
 * Enter the ice cave, kill the lagufaeth, and interact with the pile of rocks on the wall to retrieve the White Adra Gems.
 * Return to Ista on the docks.
 * Tell her that you didn't find any ore deposits, but instead found the gems. She is thrilled that the device worked, though didn't expect it to lead to inert adra. You can then:
 * Give her the gems, allowing her to refine the enchantments, netting you and moderate positive reputation with Stalwart.
 * Keep the gems for yourself, though she'll be angry that you'd choose to squander her breakthrough over some shiny trinkets. You don't get a reward, but get to keep the gems which are worth on their own.
 * Lie, and say that you couldn't find anything. Ista comes to the conclusion that the device doesn't work, but thanks you anyway and gives you for the assistance (and you get to keep the gems).

Behind the scenes

 * A couple of other triggers are present, but don't seem to be used:
 * The compass in the ore-locator spins once, then points southwest.
 * The ore-locator's compass spins in lazy circles.
 * The following addendum isn't used:
 * From the raised platform along the keep's outer wall, the device points southwest.