luster of gem
璟 centers on the bright, shining quality of a gem: its luster or gleam.
璟 combines 王 (jade/gem) with 景, which likely contributes the sound and the idea of brightness, together suggesting the luster of a gem.
The left side 王 represents a jewel, and the right side 景 suggests a bright scene. Picture a gem sparkling brilliantly in the sunlight.
For エイ, imagine an 'A'-grade gem with exceptional luster: 'A' -> エイ, and the gem shines like a top-quality jewel.
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