The Call of Earth Quest's ultimate goal is to grant you an Earth Totem, which is used to cast earth totems, as well as the Stoneskin Totem spell. You can begin this quest by speaking to Seer Ravenfeather in Camp Narache.

The first step of this quest is to head to Brambleblade Ravine, which is east-southeast of Camp Narache. Your goal there will be to kill Bristleback Shamans and take 2 of their salve. For efficiency, you may want to do this part of the quest along with the other quests in Brambleblade Ravine.

Be careful in the ravine, as the enemies inside are more challenging than those you have fought before. It shouldn't take you too long to kill the shamams, it probably will only take two to three kills. When you're done with this part of the quest, return to the Seer in Narache and prepare for the next part.

Quest: Call of Earth, Part 2
The second part of this quest is much easier than many make it out to be. Head east of Camp Narache and watch for a tall stone structure in the middle of the fields. When you get nearby, drink the Earth Sapta she gave you. The potion's affects will be manifest in a vision of a gigantic earth elemental. Speak to it to complete the quest. You'll then need to return to the quartz the elemental gave you to the Seer.

Your reward will be the Earth Totem, a unique item. You will also receive the Stoneskin totem, which reduces damage taken to yourself and nearby allies!