It's a rather unique look, but does it hold a special significance? Does it mark their status in society, their profession or their character, or is it just a fashion sense thing? Could any highly valued individual wear such a hat?
I know the army book states that they made their own death masks, but that the masks as a thing aren't unique as we can see with Tomb Guard and Khalida.
While we're at it: Would the Tomb Princes head wear mark them as nobles, or is it to show high status in general?
Oh, and the Tomb Kings' fake beards. The Tomb Guard's masks have rather short ones, while the Kings have the largest, but Necrotects have no beard at all. Is there an important distinction between beards and no beards, or is it just a flamboyant fashion choice?