Northern Crystal Pylon
The Northern Crystal Pylon is located in Un'Goro Crater.[56.5, 12.4]
Objective of
Needs to be examined the quest 
[15-30] The Northern Pylon.
Quests
You must complete [53] Making Sense of It before these quests become available.
- [15-30] Crystal Charge
- [15-30] Crystal Restore
Examined
A closer inspection of the pylon leads you to find a small table containing yellow, red, and green crystals arranged in what seems like a specific formation.
A large yellow circle of crystals is flanked on either side by a smaller circle of red crystals and another of green crystals.
You carefully take note of the colours of the crystals, knowing that J. D. would be very interested in hearing about what you have found.
J.D. explains
The Northern Pylon accepts yellow, red, and green crystals.
The focus is the energy that can be created using yellow crystals as the main source of power. There are two possible effects: one that will produce damage, and one that will negate damage.
[Crystal Charge] requires red and yellow crystals. This will produce a large explosion, stunning your enemies.
[Crystal Restore] requires yellow and green crystals. This will provide you with a healing aura.
Quotes
- Gossip
The Crystal Pylons of Un'Goro are a mystery to all. To the few inhabitants here, they are a source of legend, with much speculation as to their purpose.