1.A piece of jewelry so ostentatiously expensive that it is fit for royalty.
2.A weapon (or any other object) that is incredibly important and hidden from sight (in reference to King Tut's hidden tomb).
Casual: Rolls gold, King Tut Piece, flooded with boulders..
Ghostface Killah: Oh shit! Bookhead, just bought a 5, G had a King Tut Piece