help with golden key-like item

[Raine90]

Spoiler: show

hi everyone, when i was cleaning out the overwold of the ossean wastes i found this "Mysterious gem"
its on the top right corner where the golden keys are, and for the heck of it, i cant seem to figure what to do with it >.>

i unreavaled the whole map, searched it trough over and over again and i cant find any responding object to it.
it says on the gem "the gem looks as if its an eye of an ancient beast" so i thought it might had smth to with the sphinx or whater, but that dont seem to be case either

can anyone enlighten me on this

[Ragnar119]

There is a big skeleton dragon, you need to put it in it skull.

[mhanew]

Where exactly is this dragon skeleton? I crossed all of the area and was unable to find it?

[carlosjuero]

Make sure tool tips are always on [the magnifying glass icon] and look for a big skull with a small hole labeled "Mysterious Hole". When I found the gem it was right next to the skull.

[Deadnoob]

Make sure tool tips are always on [the magnifying glass icon] and look for a big skull with a small hole labeled "Mysterious Hole". When I found the gem it was right next to the skull.

Same here. The skull was only a few steps away from the gem drop for me.