Futunomitama no Turugi

The Futunomitama no Turugi(Antiquity in the English Anime) is a stone sword that is owned by the Asakura Family

About
Futunomitama no Turugi is a red stone sword that have been treasured by the Asakura Family for many generations. According to Asakura Hao it was once owned by a sword god and even though it's only made of rock, it is the perfect medium to create a sword oversoul. That sword which slumbers in a storage room of the Asakura Family, always creates a stir in the world when surfaced since it's a national treasure.

It was used by Asakura Yohken to kill his ancestor Hao, when he reincarnated into the Patch Tribe. 500 years later it was used by Asakura Yoh as a a secondary medium for his Over Soul during the second rounds of the Shaman Fight. Yoh's son, Asakura Hana would eventually inherit it and used as his main medium for his Over Soul.