I already done Black Mountain Clan quests and the Isle of Despair but i've sold all the crystals so i can't do the glasses now. Where can i find 2 of them now?
You need them, so you probably will never find them again. :smile: Else try a forum search, it's been discussed before.
Kathorn Crystals are very common, you can try to buy it from "wise men/woman", or other sources. I found many in BMC mines. Try there again, maybe you missed some.
You can also check with the people you sold it too. Sometimes they have it still. Sometimes not. Too bad you returned from the isle of despair there is a set of glassess on the isle.
if you wander the morhiban plains, you'll be attacked repeatedly by orcs... sometimes they carry crystals...