I answered the bow of shadows for example.
Like many other artifacts it reveals it self during a quest,in this case a lgnpc-mod which you easily muck up if you just go there outside of that quest.Whitout lgnpc no quest as I know off ?
My guess is that for new players it is part of the fun to discover those artifacts during quests without knowing about them beforehand,so there is an element of "spoilers" just mention them here.
On the other hand if we are careful with this it should be fine anyway,any long time player know of them already anyway
my 2 c
My second favourite is denstagmers ring btw
Not quest related btw so that one is perfectly safe