noun ダウンロード 🔗共有 石英 The most abundant mineral on the earth's surface, of chemical composition silicon dioxide, SiO2. It occurs in a variety of forms, both crystalline and amorphous. Found in every environment. Examples : "The geologist found a beautiful piece of quartz in the park. " 地質学者は公園で美しい石英の欠片を見つけた。 geology mineral material chemistry science environment nature AIとチャット語彙ゲーム読解練習