I like it when a plan comes together
The one reason why most readers are going to be coming here: Reducibles. This is a little bit of a thing that is just mentioned as a side option and then never talked about again. And the amount of reading into and things done by folk to try and get head first into this, it leaves some people confused. That person might be you right now. This guide's for you. This guide's for all ya'll. This is gonna be all about how this side of collectables works.
If you aren't sure on how to generate good quality (note high rating), please see the Gathering Collectables page. Rotations are at the bottom if you just need a rotation or two. This page assumes you have a basic understanding of how it works.
Sand... it gets everywhere.
The whole of the system revolves around the following skill:
This general action is unlocked by the quest No Longer a Collectable. This is found as a Disciple of the Land at level 56 in Mor Dhona after completing the Main Scenario Quest "The Better Half" in Ishgard (meaning this isn't accessible until you're in Heavensward).
When you look at a variety of tooltips for different items and fish, there will be a line that says Reducible: Yes.
These items will be your typical targets for doing reducibles. To build further, lets look at the Lover's Laurel we picked up during the Gathering Collectables example:
When it comes to reducibles, the collectability of an item is important as the final collectability rating sets what the "grade" of the reduction will be. The grade of the reducible is important because it determines overall yields and what is on the loot table.
Generally you will want your collectability over 450, as that is the 5/8 grade point for where you will begin to see aetherial sands. Higher grades do not necessarily mean you will always get aethersand on reduction, but it does mean you have a better chance of getting HQ or just plain lots of it.
You have two ways to reduce:
First is your generic right click/Square menu access in your inventory. The other is via Actions and Traits > Aetherial Reduction.
This is the UI that will appear when you are confirming. Note that like many other things, you don't have to be the job listed to do the action. Just need the level requirement on that job.
And this is the confirmation window you will receive once its' done. I've never seen a reduction fail, in case anyone is wondering.
That's it! That is literally all there is to it.