two pieces of jade joined together
珏 refers to two pieces of jade joined together, emphasizing the pairing or coupling of precious jade objects.
珏 is composed of two 玉 (jade) elements placed side by side, directly representing two pieces of jade joined together.
See the two jade pieces: the right side is clearly 玉, and the left side 王 looks like another jade piece without the dot. Together they form a pair of joined jades.
For カク, imagine a pair of jade pieces clicking together with a sharp 'kak' sound: kak -> カク, as the two jades join.
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