Slay at least 6 Grungetalon gemmasters to collect some Brell baubles (auto update, un-common drop). Gemmaster's are in groups of 3 level 31 Heroic (gemmaster is no arrow, grouped with two gemcutters two down arrows) in the Brell's March area.
Slay at least 8 Living chests to collect some Underfoot stars (auto update). Living chests are 33vvv paired with Grungetalon porters 33v solo encounter. (very-uncommon drop, and there are never more than four at once. They're also located right in the entrance, so you'll be competing with everyone who comes in, even if they're not on the quest. Respawn time is at least five minutes)
Seek and destroy the thing that is revealing the magic in the gems.
Find the Gem Analyzer in Brell's March - it will be close to one of the trampler's either left or right of the gate. Reported locations: ( 73, 23, -159 ) /waypoint 72.70, 23, -159.36 ( -97, 45, -188 ) /waypoint -96.86, 45.29, -188.40.