I used a ruby on this amulet (don’t make fun of my bad judgement, i was testing it out). It gained the legend affix properly but didn’t become a legend item. I’m afraid it’ll look like I’m a cheater. I also wanted to let the devs know the gemstone might not be working properly. As far as I know items were supposed to update to their new status after adding affixes. Like a rare would turn into a crystal after using obsidian on it.
Hey! There is no way to turn a normal item to a legend item by adding set or legend affixes. You can only get a legend item through drop.