where do you even find Kathorn crystal a this point?

i need the crystal to create glasses to get to the wheel clan but i already looted and sold everything that you can find on the map because i didnt follow the main quest i had tons of these crystal but they are gone now, and i didnt even know about the glasses either because the dwarf on isle of despair wont speak to low beauty character and you cant even comeback to the isle of despair so i was stuck for ages until i finally decided to look it up online. sorry but this whole section is completely retarded and broken badly designed makes me want to quit this game honesly.