Excalibur
I'd say pulling the sword out of the stone certainly qualifies.
Excalibur.
There is no mention of a precious stone in the story of King Arthur. However, the famous sword Excalibur is often referred to as the Sword in the Stone.
Uhhh . . . the Knights of the Round Table?
igraine
Merlin
Knights
The Lich King's weapon is called Frostmourne.
Arthur
round
Ex calibur
Sir Lancelot