I've been doing some research into unraveling for relics. When you look at an item in the imbuing menu and choose to add the same property at the same intensity it already possesses, you will see the actual weighted score of the item. If its an artifact the imbuing menu will not open as it tells you the item is made from special material already and cannot be imbued. If its player made and exceptional the max weight will say 500. So far I've found 3 items, not player made and non-artifact but actual loot, that had total weights in excess of 450. They each showed 4xx/450 and the 4xx was in red, ie. the last one was 474/450. These "should" have unraveled to relics based on the last info we got from Leurocian. However each one yielded only 1 enchanted essence. It appears to me the code is ONLY yielding relics from artifacts. I still need to test exceptional player items over 450. If the only source for relics is going to be from artifacts then the imbuing skill has been extremely nerfed.