This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
瑮 combines 王 (jade) with 栗, which likely contributes the sound. The exact historical development is uncertain.
The left side 王 suggests jade, and the right side 栗 looks like a chestnut tree. Imagine a beautiful jade ornament shaped like a chestnut, but its exact meaning is unclear.
For リツ, imagine a beautiful jade piece that fits perfectly into a ritzy display: ritzy -> リツ.