A Taste of History

[item=87779] drop from Mogu mobs while doing [faction=1269] quests in the Vale of Eternal Blossoms. [object=214388] are located in the Guo-Lai Halls (northwest Vale of Eternal Blossoms). There are several spawn points and depending on what phase of your reputation with [faction=1269], some of the locations may be behind closed doors. Right now it appears that only 2-3 spawn points are accessible at all times, and if they aren't there for you, it may mean that someone else recently opened one (respawn timer is unknown) or they may spawned in one of the more numerous spawn points you can't reach. Early on, luck will play a factor on whether you can see one of these, until more people reach higher reputation to get to the other spawn points. Opening a Cache will complete A Taste of History.

Your first opportunity to more easily access the closed off areas is at Honored reputation only while you are on The Secrets of Guo-Lai. During this quest, you have access to the Hall of Statues.

Later when you reach Revered, you'll get a quest chain starting with Battle Spear of the Thunder King which opens all the hidden areas of the Halls and likely will see far more Caches than you have keys to open.

Locations I've seen:
Entry Hallway - (47,85) between two statues
corner of first room
Hall of Statues
Guo-Lai Ritual Chamber - (65,72)
Hall of the Serpent - (54,17) (59,13) (58,6) (71,27) (50,62)

Sampling of contents:
1. ~38g, [item=90816], [item=90815], Spirit of Harmony, [item=90458] x 6, and [item=83844] (I'm a Jewelcrafter)
2. ~38g, [item=90815], [item=90458] x 6
3. 21g, Great Pandaren Banquet, Spirit of Harmony, and [item=90458] x 4

The keys are obtainable even while neutral with the Golden Lotus.

Make sure you loot the chest completely. If you, like me, get excited about a jc pattern and try to learn immediately, the chest will snap shut again and recquire another key to open.