Selenium (element)
硒 centers on the chemical element selenium, a nonmetal often found in minerals and used in electronics and glassmaking.
硒 is a modern character created to represent the element selenium. It combines 石 (stone/mineral) with 西, which likely contributes the sound セイ.
The left side 石 means stone or mineral, and the right side 西 looks like a stylized container. Picture selenium being extracted from a mineral inside a western-style flask.
For セイ, imagine saying 'say' as you point to a selenium sample: say -> セイ, and the mineral speaks its name.
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