well.. how do you give the crystals? I'm annoy to buy objects and transform them @.@ it is sooooo looooong to do.. and right to refresh the memory, the formalities of rarity for the crystals have be change?
ps sorry for the english :P
Any item, no matter the rarity, can give you a crystal. Only higher rarity items are a sure bet though.
Fastest way to get crystals is to buy them from someone else who has put the tedious effort into it. ;)
Unfortunately, if you don't make them yourself, you'll have to buy them off of someone else who has made them. Throwing items into the machine are the only way you can get crystals, and it's cheaper to make them yourself by a long shot.
It does get annoying though, I will grant you that. I spent about 8mil sP and 4 hours fragging crystals this morning. It's costly and takes forever to get the number of crystals you want, but that's the point. It's not really supposed to be easy.
I might be slightly off with the cutoffs, but items that are r66-r89 always give you one crystal. Items r90-98 can potentially give you two crystals, and r99 items can give as many as 3.