ok, i was wondering if it was something crazy like you have to discover all other artifacts then this unlocks.. lol to me it looks like a version of the explorers league emblem
Like all the other threads on this topic, it seems like no one knows for sure. Some say its just a place-holder for updates (seems kind of lazy for blizz to leave it like that ingame).... Some say that its something "special" that unlocks after you find everything...... I have gone mad looking for the answer myself....
there was a another thread about this, where someone had contacted a GM askin for it, and the GM wouldn't confirm if it was placeholder or you'd have to continue digging to find out... wouldn't suprise me though if it turns out to be something special once you find _EVERYTHING_