Shinzaho (Holy Throne) is an artifact that is required to summon a beast god. The artifact has many versions. It is arguably the base topic of Fushigi Yuugi's second season since the other half of the series mentions it a lot.
The Shinzaho of Genbu first appears in the series. It is located in the capital city of Hokkan, Touran. It is Oracle Anlu's parting gift is a key artifact in Takiko's quest to summon Genbu: not only is it able to detect where the remaining Celestial Wariors are, but it eventually becomes one of the Shinzahos Miaka requires in order to summon Suzaku. In Fushigi Yuugi: Genbu Kaiden, it was stated that the shinzaho had Takiko's last wish held in there. It was guarded by Tomite and Hikitsu. Nakago
It is a hand-mirror belonging to Suzuno, which she apparently carried during the Summoning Ceremony of Byakko. It is guarded by one of the Byakko Seven, Tatara, after Suzuno leaves the world. The shinzaho sprouts from a seed that he keeps hidden and blooms like a flower.
SuzakuMiaka's Shinzaho is first revealed in the first OVA as the ring she wore when she and Tamahome had an unofficial wedding.
Miaka had a second shinzaho which was revealed in Fushigi Yuugi Eikoden as her and Taka's unborn child. The second Shinzaho happened because in the second OVA, it was shown that she and Tamahome once again called Suzaku to completely seal Tenkou away.
Mayo Sakaki's "shinzaho" was the ring on her finger.
The Shinzaho of Seiryuu is revealed in Fushigi Yuugi Novels: Sanbou Den (The Legend of the Three Talisman), it is the teardrop earring from the summoning ceremony of Seiryuu. Nakago's spirit is the guardian of the Seiryuu's shinzaho.