noun
A common mineral composed of silicon dioxide. Used in glassmaking, electronics, and as a gemstone.
石英はガラスの原料として使われる。
Quartz is used as a raw material for glass.
この時計は石英で動く。
This watch runs on quartz.
水晶 specifically refers to clear, colorless quartz crystal, while 石英 is the broader mineral term for quartz in any form.
From Chinese 石英 (shíyīng), literally 'stone flower/brilliance', referring to the mineral's crystalline appearance.