The Crystals and Pylons of Un'goro Crater

There's something else you can do with all those collectible crystals in Un'goro crater. You can exchange them for new crystals with a variety of abilities, such as a heal over time, shield, AoE fire damage, buffs, etc..

Background:
You may remember the following quests in Un'goro which introduce you to all the crystals and pylons:

Crystals of Power in which you bring 7 of each color crystal to J.D. Collie, the gnome in the cave.

Visit the Eastern Pylon

Visit the Northern Pylon

Visit the Western Pylon

and finally:

Making Sense of it in which you receive the Crystal Pylons User's Manual

What Next:
The User's Manual tells you which crystals to take to which pylon, and what you can exchange them for.

Each pylon has two unique crystals it can give you back.

Each exchange will require 10 each of two different color crystals

Here's a picture at the Eastern Pylon:


And these tables show the exchanges available at each Pylon:

Northern Pylon

Turn in:	Receive:
Red	Crystal Charge Inflicts 383 to 517 fire damage to targets in a 3 yard radius	-
Yellow		Crystal Restore Heals the target of 670 damage over 15 sec.
Green	-

Eastern Pylon

Turn in:	Receive:
Green	Crystal Force Increases the target's Spirit by 30 for 30 min.	-
Blue		Crystal Spire Use: A crystal shield surrounds the friendly target, doing 12 damage to anyone who hits her. Lasts 10 min.
Yellow	-

Western Pylon

Turn in:	Receive:
Blue	Crystal Yield Decreases an enemy target's Armor by 200 for 2 min.	-
Red		Crystal Ward Use: Increases the target's Armor by 200 for 30 min.
Green	-

In what was less an experiment and more necessity than I'd like to admit, I would often load up for bear (dinosaur?) with all of my newly exchanged crystals and do some elite mob hunting. Although I should note that the new crystals and buffs that you get can be used anywhere and are not limited to use in Un'goro Crater.

Happy Crystal Hunting!