Last Updated
：2025/11/20
corundum
IPA(Pronunciation)
Noun
countable
uncountable
Japanese Meaning
極めて硬い鉱物。酸化アルミニウム（Al₂O₃）の一種で、サファイアやルビーとして宝石に用いられる。また、研磨材としても利用される。
（ plural ）
Quizzes for review
(mineralogy) An extremely hard mineral, a form of aluminum oxide with the chemical formula Al₂O₃, that occurs in the form of the gemstones sapphire and ruby; it is used as an abrasive.
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corundum
The jeweler explained that the deep blue stones were actually corundum, a crystalline form of aluminum oxide prized for its hardness.
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The jeweler explained that the deep blue stones were actually corundum, a crystalline form of aluminum oxide prized for its hardness.
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