kind of mineral
硇 refers to a specific kind of mineral. Its meaning is narrow and technical, with no clear broader conceptual center beyond its mineral identity.
硇 combines the stone radical 石 with the phonetic component 囟. The exact historical development is uncertain, but it likely follows the standard pattern of mineral names using 石 to indicate a stone or mineral and 囟 for sound.
The stone radical 石 tells you it is a mineral. The right side 囟 looks like a skull or a container, so imagine a rare mineral stored inside a stone skull.
For ドウ, picture a dough-like mineral paste being shaped: dough -> ドウ, and the stone 石 is the mineral.
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