jade look alike stone
璡 refers to a stone that resembles jade, a jade-like stone. Its meaning is narrow and concrete, without broader abstract extensions.
璡 combines the jade radical 王 with 進, which likely contributes the sound シン. The character is rare, and its exact historical development is uncertain.
The left side 王 (jade) and the right side 進 (advance) suggest a stone that advances toward being jade but isn't quite there: a jade-like stone.
For シン, imagine a thin slice of this jade-like stone: thin -> シン, and the stone's appearance is almost like real jade.
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