I have no idea what is being said. I thought it was weapons that were spiritbonded into materia, which you can then use on weapons. Materia is spiritbonded too?
Every piece of gear that doesn't have the text "Convertible: No" at the bottom can be spiritbonded. When the spiritbond with a piece of gear reaches 100%, you can Press Square/Right-Click on the gear item to open up the submenu, and select 'Convert'.
Convert turns that 100% spiritbonded gear item (be it pants or rings or anything) into Materia.
- Equip pants
- Kill 1 enemy
- Pants are now bound to you, and cannot be sold on market board, only to NPC
- Kill lots of enemies
- Pants reaches 100% spiritbond (white bar next to your gear icon)
- Convert
- Your pants become a materia. (You now have no pants.)
Spiritbond with a piece of gear increases depending on the amount of exp the gear piece gets.
- Lvl 50 pants > Kill Lvl 1 enemies > Might take several thousand Lvl 1 enemies before 100% spiritbond
- Lvl 1 pants > Kill Lvl 1 enemies > Should spiritibond at a reasonable rate
Two ways to speed up the spiritbond process is to
- Wear HQ gear. HQ items spiritbond faster than normal quality items.
- Meld materia to the gear item. Each materia melded increases the spiritbond rate by a flat percentage. You can meld any garbage materia in and it will still have the same rate, so don't waste your valuable materia on this.
Obviously, aside from maximizing the rate at which a piece of gear spiritbonds, you also ideally want to kill enemies as fast as you can and farm a lot of exp for your gear to get them to spiritbond faster. For that, there are several locations where Lvl 50 enemies spawn fairly quickly in a small area, that you can theoretically massacre for your gear.