Gold Kryptonite with lead case

Gold Kryptonite permanently removes superpowers from kryptonians.
Superman uses Gold Kryptonite to remove the powers of criminal Kryptonians inside the pocket universe.
In the movie Superman II, Superman steps into a chamber inside the Fortress of Solitude to have his superpowers removed.
This chamber must have been powered by Gold Kryptonite.
Jer-El removes Clark Kent's superpowers in an episode of Smallville.
Maybe Jor-El accomplished this using some Gold Kryptonite somewhere off camera.
Scientists have measured the effective range of Gold Kryptonite to be between 2 feet, and 20 feet.

Gold Kryptonite: 1/2 inch (1.27cm)

Lead Case: 3.75 inches x 2 inches x 3/4 inch (9.525 cm x 5.08 cm x 1.9 cm)