This property defines the Unicodes which belongs to Yijing Hexagram Symbols block
Characters like ䷀,䷁,䷂, etc. are listed under Yijing Hexagram Symbols Block.
64 Characters are present in Yijing Hexagram Symbols Block starting with the Unicode point U+4DC0 that represents the character ䷀.
Currently, as per latest version 15.0.0, Unicode supports 328 number of Block. Here are a few examples - Latin Extended E,Adlam,Aegean Numbers, etc.