DrShodax

It don't work , the game won't let me sell a weapon if a gem is attached... of course the quest is completed and the npc don't care of me anymore.

Put it on a crap weapon and sell that Weapon to a NPC dont work , game said you need to detach item on it in order to sell it. so can't sell it , can't drop it, can't destroy it , can't store it. Some player have that issue since 2015 ... it was 8 years ago ...