noun🔗ShareCorindonAn 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."Because of its hardness, corundum is used in sandpaper to smooth rough wood. "En raison de sa dureté, le corindon est utilisé dans le papier de verre pour lisser le bois brut.mineralmaterialgeologysubstancechemistryscienceChat with AIVocabulary GamePractice Reading
