By using the armor and weapons that you equip yourself with, you will generate "attachment points"* and when your attachment points reach 100% you will be able to convert that weapon or armor into "materia." This is known as "materia conversion." "Materia" is a crystallized form of the weapon and armor’s stats that the player has used and formed an attachment to.
During the materia conversion process, there will be fluctuations that result in NQ stat materia, as well as HQ stat materia, even when using the same type of item. However, even the NQ stat material will have beneficial stats.
Also, you will be able to purchase and trade materia freely.
Crafters will be able to utilize the catalysts that gatherers obtain and attach a single materia to an item (there is no chance of failure). The materia you will be able to attach will depend on the type of weapon and the type of stat that matches the equipment slot. There are a variety of different combinations of materia that can be attached to each equipment slot’s item, so each player will need to decide what they want to pursue.
In addition to this, you will also be able to remove materia from items that have had materia attached to them. However, upon removal you will lose the materia, so you should probably only remove it when you definitely have a better upgrade to replace it with
I'm very excited about this!