how does achelmist work in terms of extracting equips

like rings? does it revert you back the equip to its core ingredients?

Also, once you reach lv. 10 of a particular skill, and you change jobs, when you change back to it will you still be at lv. 10?

First, it just gives you item crystals, no matter what your extracting.
Second, No, once you change professions the one you had before resets.

what are item crystals?

Item Crystals are similar to Monster Crystals, except that they're only obtained from extracting equipment. They're used in making many things.

oh you mean monster crystals. Gotcha. So what do most ppl use the alchemy skill to do? disassemble equips? i guess to get monster crystals? which skill level do most ppl get alchemy up to?

oh you mean monster crystals. Gotcha. So what do most ppl use the alchemy skill to do? disassemble equips? i guess to get monster crystals? which skill level do most ppl get alchemy up to?

they aren't monster crystals anymore, they are item crystals, they look and serve the same purpose, but due to the method of obtaining them, they are something completely different (not to mention, monster crystals are useless.)

oh you mean monster crystals. Gotcha. So what do most ppl use the alchemy skill to do? disassemble equips? i guess to get monster crystals? which skill level do most ppl get alchemy up to?

Well alchemist can make a bunch of buff potions, from stats to max hp and mp, also you can make pretty cheap hp and mp pots and this pretty nice ability that lets you fuse two of the same item in order to try for better stats with a chance to get potential on it.