Also, these statues are known as the oldest example to use crystal inlays for eyes of a statue (the technique called 'gyokugan' in Japanese) among the statues whose production dates have been identified so far.
本三尊像は、玉眼（像の眼の部分に水晶を嵌め込む技法）を用いた像で制作年代の判明する最古例としても知られる。